Nanotechnology and water treatment: applications and emerging opportunities

Progress in the Sustainable Development of Biobased (Nano)materials for Application in Water Treatment Technologies

Water pollution remains a widespread problem, affecting the health and wellbeing of people around the globe. While current advancements in wastewater treatment and desalination show promise, there are still challenges that need to be overcome to make these technologies commercially viable. Nanotechnology plays a pivotal role in water purification and desalination processes today. However, the release of nanoparticles (NPs) into the environment without proper safeguards can lead to both physical and chemical toxicity. Moreover, many methods of NP synthesis are expensive and not environmentally sustainable. The utilization of biomass as a source for the production of NPs has the potential to mitigate issues pertaining to cost, sustainability, and pollution. The utilization of biobased nanomaterials (bio-NMs) sourced from biomass has garnered attention in the field of water purification due to their cost-effectiveness, biocompatibility, and biodegradability. Several research studies have been conducted to efficiently produce NPs (both inorganic and organic) from biomass for applications in wastewater treatment. Biosynthesized materials such as zinc oxide NPs, phytogenic magnetic NPs, biopolymer-coated metal NPs, cellulose nanocrystals, and silver NPs, among others, have demonstrated efficacy in enhancing the process of water purification. The utilization of environmentally friendly NPs presents a viable option for enhancing the efficiency and sustainability of water pollution eradication. The present review delves into the topic of biomass, its origins, and the methods by which it can be transformed into NPs utilizing an environmentally sustainable approach. The present study will examine the utilization of greener NPs in contemporary wastewater and desalination technologies.

Environmental significance of PAH photoproduct formation: TiO2 nanoparticle influence, altered bioavailability, and potential photochemical mechanisms

Interactions between polycyclic aromatic hydrocarbons (PAHs) and titanium dioxide (TiO2) nanoparticles (NPs) can produce unforeseen photoproducts in the aqueous phase. Both PAHs and TiO2-NPs are well-studied and highly persistent environmental pollutants, but the consequences of PAH-TiO2-NP interactions are rarely explored. We investigated PAH photoproduct formation over time for benzo[a]pyrene (BaP), fluoranthene (FLT), and pyrene (PYR) in the presence of ultraviolet A (UVA) using a combination of analytical and computational methods including, identification of PAH photoproducts, assessment of expression profiles for gene indicators of PAH metabolism, and computational evaluation of the reaction mechanisms through which certain photoproducts might be formed. Chemical analyses identified diverse photoproducts, but all PAHs shared a primary photoproduct, 9,10-phenanthraquinone (9,10-PQ), regardless of TiO2-NP presence. The computed reaction mechanisms revealed the roles photodissociation and singlet oxygen chemistry likely play in PAH mediated photochemical processes that result in the congruent production of 9,10-PQ within this study. Our investigation of PAH photoproduct formation has provided substantial evidence of the many, diverse and congruent, photoproducts formed from physicochemically distinct PAHs and how TiO2-NPs influence bioavailability and time-related formation of PAH photoproducts.

Dual stimulus-responsive renewable nanoadsorbent for selective adsorption of low-density lipoprotein in serum

Selective removal of ultra-high low-density lipoprotein (LDL) from the blood of hyperlipemia patients using hemoperfusion is considered an efficient method to prevent the deterioration of atherosclerotic cardiovascular disease. Based on the exceptional structure-function properties of multistimulus-responsive materials, we developed a magnetic photorenewable nanoadsorbent (Fe3O4@SiO2@Azo-COOH) with outstanding selectivity and regenerative characteristics, featuring functionalized azobenzene as the ligand. The dual-stimulus response endowed Fe3O4@SiO2@Azo-COOH with rapid separation and photoregenerative properties. The adsorbent demonstrated excellent removal efficiency of LDL with an adsorption capacity of 15.06 mg/g, and highly repetitive adsorption performance (≥5 cycles) under irradiation. Fe3O4@SiO2@Azo-COOH also exhibited remarkable adsorption properties and selectivity in human serum, with adsorption capacities of 10.93, 21.26 and 9.80 mg/g for LDL, total cholesterol and triglycerides and only 0.77 mg/g for high-density lipoprotein (HDL), resulting in a 93% selective adsorption difference (LDL/HDL). Complete green regeneration of the nanoadsorbent was achieved through a simple regeneration process, maintaining a recovery rate of 99.4% after five regeneration experiments. By combining dynamic perfusion experiment with micromagnetic microfluidics, the LDL content decreased by 16.6%. Due to its superior adsorption capacity and regenerative properties, the dual stimulus-responsive nanosorbent is considered a potential hemoperfusion adsorbent.

Neem plant extract-assisted synthesis of CeO2 nanoparticles for photocatalytic degradation of piroxicam and naproxen

Piroxicam and naproxen are well-known non-steroidal anti-inflammatory drugs that are frequently detected in aquatic environments due to their widespread usage and improper disposal practices. This research investigates the photocatalytic degradation of these drugs by using CeO2 nanoparticles. The nanoparticles were synthesized by using Azadirachta indica plant extract and were characterized through various characterization techniques such as UV-visible spectroscopy, FTIR spectroscopy, SEM, EDX, and XRD. The photocatalytic degradation of piroxicam and naproxen using CeO2 nanoparticles led to the efficient removal of these pharmaceutical drugs in a short time duration with photodegradation efficiencies of 89% and 97% for naproxen and piroxicam, respectively. The photodegradation reaction was found to follow pseudo-order first-order kinetics. The recyclability of the catalyst was also studied for up to six cycles where the degradation efficiency was maintained at 100% till the 2nd cycle and was decreased by 11 and 13% for piroxicam and naproxen respectively after the 6th cycle. The current work focused on the achievement of sustainable development goals (SDGs) for water purification via environmentally benign nanoparticles to remedy water pollution as it is the most prevalent issue in developed and underdeveloped countries throughout the world.

Estimation of genomic and mitochondrial DNA integrity in the renal tissue of mice administered with acrylamide and titanium dioxide nanoparticles

The Kidneys remove toxins from the blood and move waste products into the urine. However, the accumulation of toxins and fluids in the body leads to kidney failure. For example, the overuse of acrylamide and titanium dioxide nanoparticles (TiO2NPs) in many food and consumer products increases human exposure and risks; however, there are almost no studies available on the effect of TiO2NPs coadministration with acrylamide on the integrity of genomic and mitochondrial DNA. Accordingly, this study was conducted to estimate the integrity of genomic and mitochondrial DNA in the renal tissue of mice given acrylamide and TiO2NPs. To achieve this goal, mice were administrated orally TiO2NPs or/and acrylamide at the exposure dose levels (5 mg/kg b.w) and (3 mg/kg b.w), respectively, five times per week for two consecutive weeks. Concurrent oral administration of TiO2NPs with acrylamide caused remarkable elevations in the tail length, %DNA in tail and tail moment with higher fragmentation incidence of genomic DNA compared to those detected in the renal tissue of mice given TiO2NPs alone. Simultaneous coadministration of TiO2NPs with acrylamide also caused markedly high elevations in the reactive oxygen species (ROS) production and p53 expression level along with a loss of mitochondrial membrane potential and high decreases in the number of mitochondrial DNA copies and expression level of β catenin gene. Therefore, from these findings, we concluded that concurrent coadministration of acrylamide with TiO2NPs augmented TiO2NPs induced genomic DNA damage and mitochondrial dysfunction through increasing intracellular ROS generation, decreasing mitochondrial DNA Copy, loss of mitochondrial membrane potential and altered p53 and β catenin genes expression. Therefore, further studies are recommended to understand the biological and toxic effects resulting from TiO2NPs with acrylamide coadministration.

Multifactorial role of nanoparticles in alleviating environmental stresses for sustainable crop production and protection

In the era of dire environmental fluctuations, plants undergo several stressors during their life span, which severely impact their development and overall growth in negative aspects. Abiotic stress factors, especially moisture stress i.e shortage (drought) or excess (flooding), salinity, temperature divergence (i.e. heat and cold stress), heavy metal toxicity, etc. create osmotic and ionic imbalance inside the plant cells, which ultimately lead to devastating crop yield, sometimes crop failure. Apart from the array of abiotic stresses, various biotic stress caused by pathogens, insects, and nematodes also affect production. Therefore, to combat these major challenges in order to increase production, several novel strategies have been adapted, among which the use of nanoparticles (NPs) i.e. nanotechnology is becoming an emerging tool in various facets of the current agriculture system, nowadays. This present review will elaborately depict the deployment and mechanisms of different NPs to withstand these biotic and abiotic stresses, along with a brief overview and indication of the future research works to be oriented based on the steps provided for future research in advance NPs application through the sustainable way.

A hypothetical model of multi-layered cost-effective wastewater treatment plant integrating microbial fuel cell and nanofiltration technology: A comprehensive review on wastewater treatment and sustainable remediation

Wastewater management has emerged as an uprising concern that demands immediate attention from environmentalists worldwide. Indiscriminate and irrational release of industrial and poultry wastes, sewage, pharmaceuticals, mining, pesticides, fertilizers, dyes and radioactive wastes, contribute immensely to water pollution. This has led to the aggravation of critical health concerns as evident from the uprising trends of antimicrobial resistance, and the presence of xenobiotics and pollutant traces in humans and animals due to the process of biomagnification. Therefore, the development of reliable, affordable and sustainable technologies for the supply of fresh water is the need of the hour. Conventional wastewater treatment often involves physical, chemical, and biological processes to remove solids from the effluent, including colloids, organic matter, nutrients, and soluble pollutants (metals, organics). Synthetic biology has been explored in recent years, incorporating both biological and engineering concepts to refine existing wastewater treatment technologies. In addition to outlining the benefits and drawbacks of the current technologies, this review addresses novel wastewater treatment techniques, especially those using dedicated rational design and engineering of organisms and their constituent parts. Furthermore, the review hypothesizes designing a multi-bedded wastewater treatment plant that is highly cost-efficient, sustainable and requires easy installation and handling. The novel setup envisages removing all the major wastewater pollutants, providing water fit for household, irrigation and storage purposes.

Conversion of novel tannery sludge-derived biochar/TiO2 nanocomposite for efficient removal of Cr (VI) under UV light: photocatalytic performance and mechanism insight

An investigation on the reduction of Cr (VI) pollutant from tannery effluents using TiO₂, SB/TiO₂, and c-SB/TiO₂ nano photocatalysts was presented in this study. For the preparation of Biochar-based TiO₂ photocatalyst (SB/TiO₂), tannery sludge was utilized as a precursor. Hydrothermal pre-treatment was adopted to prepare chemically activated SB/TiO₂ and SB/TiO₂ nanocomposites. The morphology, crystal structure, optical properties, and elemental composition of the prepared catalysts were analyzed by XRD, FT-IR, SEM-EDX, BET analysis, ZPC, PL, TGA, and Raman spectroscopy. The band gap analysis of Photocatalyst was measured using a DRS instrument, and band gap energy of 3.39 eV was obtained for c-SB/TiO₂ photocatalyst. The developed c-SB/TiO₂ catalyst exhibits a larger specific surface area of 646.85 m²/g than TiO₂ and SB/TiO₂ (74.58 m²/g and 573.74 m²/g), respectively. The enhanced photocatalytic activity for the pollutant removal was achieved by the photocatalyst due to their wide band gap and effective charge separation. The kinetic rate constant was achieved in the pseudo-first-order model, which fits well for the reduction of Cr (VI). Furthermore, at the optimal conditions of 10 mg/L contaminant concentration, pH 2, and 0.5 g/L catalyst dosage, 98.56% reduction was observed after 180 min of reaction. The OH acts as a major removal pathway for Cr (VI) contaminants with more than 50% reduction in COD. This study proves that c-SB/TiO₂ photocatalysts can remove toxic contaminants under UV light irradiation with good recycling performance up to 5 times.

High-efficiency degradation catalytic performance of a novel Angelica sinensis polysaccharide-silver nanomaterial for dyes by ultrasonic cavitation

Currently, the polluted wastewater discharged by industry accounts for the major part of polluted bodies of water. As one of the industrial wastewaters, dye wastewater is characterized by high toxicity, wide pollution, and difficulty in decolorization degradation. In this paper, a novel composite nanomaterial catalyst of silver was prepared by using Angelica sinensis polysaccharide (ASP) as a reducing and stabilizing agent. And the optimum reaction conditions explored are V_AgNO3 = 5 mL (300 mM) and v_ASP = 7% (w/v) for 6 h at 90 °C. In addition, the ASP-Ag nanocatalyst was characterized by several techniques. The results demonstrated that ASP-Ag nanoparticles were successfully synthesized. Degradation rate, which provides a numerical visualization of the percentage reduction in pollutant concentration. With the wrapping of ASP, the ultrasonic catalytic degradation rates of different organic dyes including rhodamine B (RB), methylene blue (MB), and methyl orange (MO) were from 88.2%, 88.7%, and 85.2% to 96.1%, 95.2% and 93.5% at room temperature, respectively. After the experiments, when c_dyes = 10 mg/L, the highest degradation rate can be observed under c_APS-AgNPs = 10 mg/L with the most powerful cavitation frequency f = 59 kHz. The effect of ultrasonic frequency on the acoustic pressure distribution in the reactor was investigated by using COMSOL Multiphysis^@ software to propose the mechanism of ultrasonic degradation and the mechanism was confirmed by OH radical trapping experiments. It indicates that OH produced by the ultrasonic cavitation effect plays a determinant role in the degradation. And then, the intermediate products of the dye degradation process were analyzed by gas chromatography and mass spectrometry (GC-MS), and the possible degradation processes of dyes were proposed. The resulting products of degradation are SO₄^2-, NH₄⁺, NO₃^-, N₂, CO₂ and H₂O. Finally, the recycling degradation experiments showed that catalyst maintains a high degradation rate within reusing 5 cycles. Thus, this catalyst is highly efficient and recyclable.

Bioinorganic Nanoparticles for the Remediation of Environmental Pollution: Critical Appraisal and Potential Avenues

Nowadays, environmental pollution has become a critical issue for both developed and developing countries. Because of excessive industrialization, burning of fossil fuels, mining and exploration, extensive agricultural activities, and plastics, the environment is being contaminated rapidly through soil, air, and water. There are a variety of approaches for treating environmental toxins, but each has its own set of restrictions. As a result, various therapies are accessible, and approaches that are effective, long-lasting, less harmful, and have a superior outcome are extensively demanded. Modern research advances focus more on polymer-based nanoparticles, which are frequently used in drug design, drug delivery systems, environmental remediation, power storage, transformations, and other fields. Bioinorganic nanomaterials could be a better candidate to control contaminants in the environment. In this article, we focused on their synthesis, characterization, photocatalytic process, and contributions to environmental remediation against numerous ecological hazards. In this review article, we also tried to explore their recent advancements and futuristic contributions to control and prevent various pollutants in the environment.

Assessment of hazardous impact of nickel oxide nanoparticles on biochemical and histological parameters of gills and liver tissues of Heteropneustes fossilis

BACKGROUND

The aim of the present study was to assess the hazardous impact of nickel oxide nanoparticles (NiO NPs) on gills and liver of Heteropneustes fossilis.

METHODS

Fishes were treated with four concentrations of NiO NPs for a period of 14 days. Nickel accumulation, lipid peroxidation, antioxidant enzymes activities (superoxide dismutase, catalase, glutathione s transferase & glutathione reductase), liver enzymes activities (aspartate amino transferase, alanine transaminase, & alkaline phosphatase), Na⁺/K⁺ ATPase activity, FTIR, metallothionein content, ethoxyresorufin-o-deethylase activity, immunohistochemistry, histology and scanning electron microscopy were analyzed in both gills and liver tissues.

RESULTS

Results revealed increased accumulation of nickel in both the tissues of exposed fishes. Lipid peroxidation and activities of different antioxidant enzymes increased (except superoxide dismutase) in both the tissues after exposure. Fluctuations in liver enzymes activities and variation in the activity of Na⁺/K⁺ ATPase were also observed. FTIR data revealed shift in peaks position in both the tissues. Level of metallothionein and its expression as well as activity of ethoxyresorufin-o-deethylase and expression of CYP1A also increased in both the target tissues of treated fishes. Furthermore, histological investigation and scanning electron microscopy showed structural damages in gills as well as liver tissues of exposed fishes.

CONCLUSION

Our results suggest that NiO NPs cause deteriorating effects on the gill and liver tissues of fish, therefore effluents containing these nanoparticles should be treated before their release into water bodies.

Colloidal nanomaterials for water quality improvement and monitoring

Water is the most important resource for all kind forms of live. It is a vital resource distributed unequally across different regions of the globe, with populations already living with water scarcity, a situation that is spreading due to the impact of climate change. The reversal of this tendency and the mitigation of its disastrous consequences is a global challenge posed to Humanity, with the scientific community assuming a major obligation for providing solutions based on scientific knowledge. This article reviews literature concerning the development of nanomaterials for water purification technologies, including collaborative scientific research carried out in our laboratory (nanoLAB@UA) framed by the general activities carried out at the CICECO-Aveiro Institute of Materials. Our research carried out in this specific context has been mainly focused on the synthesis and surface chemical modification of nanomaterials, typically of a colloidal nature, as well as on the evaluation of the relevant properties that arise from the envisaged applications of the materials. As such, the research reviewed here has been guided along three thematic lines: 1) magnetic nanosorbents for water treatment technologies, namely by using biocomposites and graphite-like nanoplatelets; 2) nanocomposites for photocatalysis (e.g., TiO2/Fe3O4 and POM supported graphene oxide photocatalysts; photoactive membranes) and 3) nanostructured substrates for contaminant detection using surface enhanced Raman scattering (SERS), namely polymers loaded with Ag/Au colloids and magneto-plasmonic nanostructures. This research is motivated by the firm believe that these nanomaterials have potential for contributing to the solution of environmental problems and, conversely, will not be part of the problem. Therefore, assessment of the impact of nanoengineered materials on eco-systems is important and research in this area has also been developed by collaborative projects involving experts in nanotoxicity. The above topics are reviewed here by presenting a brief conceptual framework together with illustrative case studies, in some cases with original research results, mainly focusing on the chemistry of the nanomaterials investigated for target applications. Finally, near-future developments in this research area are put in perspective, forecasting realistic solutions for the application of colloidal nanoparticles in water cleaning technologies.

Adsorption and Photocatalytic Degradation of Pesticides into Nanocomposites: A Review

The extensive use of pesticides in agriculture has significantly impacted the environment and human health, as these pollutants are inadequately disposed of into water bodies. In addition, pesticides can cause adverse effects on humans and aquatic animals due to their incomplete removal from the aqueous medium by conventional wastewater treatments. Therefore, processes such as heterogeneous photocatalysis and adsorption by nanocomposites have received special attention in the scientific community due to their unique properties and ability to degrade and remove several organic pollutants, including pesticides. This report reviews the use of nanocomposites in pesticide adsorption and photocatalytic degradation from aqueous solutions. A bibliographic search was performed using the ScienceDirect, American Chemical Society (ACS), and Royal Society of Chemistry (RSC) indexes, using Boolean logic and the following descriptors: "pesticide degradation" AND "photocatalysis" AND "nanocomposites"; "nanocomposites" AND "pesticides" AND "adsorption". The search was limited to research article documents in the last ten years (from January 2012 to June 2022). The results made it possible to verify that the most dangerous pesticides are not the most commonly degraded/removed from wastewater. At the same time, the potential of the supported nanocatalysts and nanoadsorbents in the decontamination of wastewater-containing pesticides is confirmed once they present reduced bandgap energy, which occurs over a wide range of wavelengths. Moreover, due to the great affinity of the supported nanocatalysts with pesticides, better charge separation, high removal, and degradation values are reported for these organic compounds. Thus, the class of the nanocomposites investigated in this work, magnetic or not, can be characterized as suitable nanomaterials with potential and unique properties useful in heterogeneous photocatalysts and the adsorption of pesticides.

Experimental and Numerical Investigations of Using Nanoparticles in Groundwater Remediation

The efficiency of using zeolite nano-clay and silica sand in removing iron from groundwater is investigated experimentally as an application of in situ remediation technique using permeable reactive barrier (PRB). In the first stage of the study batch experiments were conducted on coarse silica sand and fine silica gravel to determine their iron removal efficiency from contaminated water. The results showed that the removal efficiency was about 51.90% for coarse silica sand while fine silica gravel failed to reduce the iron concentration in water. A mix of zeolite nano-clay and coarse silica sand with a ratio of 1:30 was tested. It was found that iron removal efficiency significantly increases to about 99.70%. The linear adsorption isotherm was found to be the most representative for the adsorption of iron onto coarse silica sand and the mix of nano-clay and coarse silica sand with distribution coefficients equal 0.0009 and 0.001, respectively. In the second stage a glass sand tank with coarse silica sand and a mix of zeolite nano-clay and coarse silica PRBs was constructed. The sand tank was used to investigate the effect of sampling time, head difference, iron concentration, nano-clay dosage, and thickness of permeable reactive barrier on the iron removal efficiency. The results indicated that increasing iron concentration and head difference decreases iron removal efficiency. The mix of zeolite nano-clay and coarse silica sand improves iron removal efficiency. Furthermore, increasing nano-clay dosage slightly increases the removal efficiency. However, increasing the thickness of filter layer (i.e., PRB) significantly improves the removal efficiency. Finally, the experimental model data were used to test the capability of a numerical contaminant transport model to predict the removal efficiency. The MT3DMS numerical model included within the Groundwater Modeling System (GMS) was used along with the different experimental data to obtain reaction rate values as calibration parameters for linear isotherm. Reaction rates that yield modeling results matching experimental data were obtained.

Polysaccharide-based nanosystems: a review

Polysaccharide-based nanosystem is an umbrella term for many areas within research and technology dealing with polysaccharides that have at least one of their dimensions in the realm of a few hundreds of nanometers. Nanoparticles, nanocrystals, nanofibers, nanofilms, and nanonetworks can be fabricated from many different polysaccharide resources. Abundance in nature, cellulose, starch, chitosan, and pectin of different molecular structures are widely used to fabricate nanosystems for versatile industrial applications. This review presents the dissolution and modification of polysaccharides, which are influenced by their different molecular structures and applications. The dissolution ways include conventional organic solvents, ionic liquids, inorganic strong alkali and acids, enzymes, and hydrothermal treatment. Rheological properties of polysaccharide-based nano slurries are tailored for the purpose functions of the final products, e.g., imparting electrostatic functions of nanofibers to reduce viscosity by using lithium chloride and octenyl succinic acid to increase the hydrophobicity. Nowadays, synergistic effects of polysaccharide blends are increasingly highlighted. In particular, the reinforcing effect of nanoparticles, nanocrystals, nanowhiskers, and nanofibers to hydrogels, aerogels, and scaffolds, and the double network hydrogels of a rigid skeleton and a ductile substance have been developed for many emerging issues.

Design of nanomaterials for the removal of per- and poly-fluoroalkyl substances (PFAS) in water: Strategies, mechanisms, challenges, and opportunities

Due to their persistent and pervasive distribution and their adverse effects on human health, the removal of per- and polyfluoroalkyl substances (PFAS) from the environment has been the focus of current research. Recent studies have shown that engineered nanomaterials provide great opportunities for their removal by chemical, physical and electrochemical adsorption methods, or as photo- or electrocatalysts that promote their degradation. This review summarizes and discusses the performance of recently reported nanomaterials towards PFAS removal in water treatment applications. We discuss the performance, mechanisms, and PFAS removal conditions of a variety of nanomaterials, including carbon-based, non-metal, single-metal, and multi-metal nanomaterials. We show that nanotechnology provides significant opportunities for PFAS remediation and further nanomaterial development can provide solutions for the removal of PFAS from the environment. We also provide an overview of the current challenges.

Biologically Synthesized Copper Nanoparticles Show Considerable Degradation of Reactive Red 81 Dye: An Eco-Friendly Sustainable Approach

Diospyros kaki leaf extract was used in this study as a favorable basis for the synthesis of copper nanoparticles (Cu NPs). X-ray diffraction (XRD) and UV-visible spectroscopy approaches were used to characterize the biologically synthesized copper nanoparticles. The XRD analysis showed that copper nanoparticles were face-centered cubic structure. Various experimental levels like conc. of dye, concentration of Cu NPs, pH, reaction time, and temperature were optimized to decolorize reactive red 81 dye using the synthesized Cu NPs. Reactive red 81 dye was decolorized maximum using Cu NPs of 0.005 mg/L. Additionally, reactive red 81 dye was decolorized at its maximum at pH = 6, temperature = 50°C. Our study reported that chemical oxidation demand (COD) and total organic carbon (TOC) deduction efficacies were 74.56% and 73.24%. Further degradation study of reactive red 81 dye was also carried out. Cu NPs have the ability and promising potential to decolorize and degrade reactive red 81 dye found in wastewater.

A critical review on clay-based nanocomposite particles for application of wastewater treatment

Nanotechnology plays an important function in recent environmental aspects for the elimination of contaminants in the ecosystem. In recent times, nano-clay has initiated more concentration because of its distinctive physicochemical properties and characteristics. Recently, many types of research in clay-based nanocomposite were accomplished in the elimination of pollutants from water sources. Nanocomposite materials have advanced properties useful for contaminat removal such as higher surface area, thermal stability, selectivity to remove different contaminants, improved process ability, and fast decontamination. Thus, the development of clay-based composite materials is one of the upcoming directions to use effectively in water and wastewater treatment as adsorbent nanomaterials. This paper assesses the latest achievement in clay-based nanocomposite preparation, material property analysis and function for various pollutant removals. In particular, great consideration was paid to the recent progress in clay/metallic, clay-polymer, and clay-carbon composites presenting their application in the removal of different kinds of pollutants. Moreover, the mechanism of adsorption, the challenges and future perspective were also discussed to reach the optimum performance of the nanomaterials adsorbent. It is confirmed that clay-based nanocomposite materials are more cost-effective technology than conventional treatment methods.

Zinc Oxide Nanoparticles and Their Biosynthesis: Overview

Zinc (Zn) is plant micronutrient, which is involved in many physiological functions, and an inadequate supply will reduce crop yields. Its deficiency is the widest spread micronutrient deficiency problem; almost all crops and calcareous, sandy soils, as well as peat soils and soils with high phosphorus and silicon content are expected to be deficient. In addition, Zn is essential for growth in animals, human beings, and plants; it is vital to crop nutrition as it is required in various enzymatic reactions, metabolic processes, and oxidation reduction reactions. Finally, there is a lot of attention on the Zn nanoparticles (NPs) due to our understanding of different forms of Zn, as well as its uptake and integration in the plants, which could be the primary step toward the larger use of NPs of Zn in agriculture. Nanotechnology application in agriculture has been increasing over recent years and constitutes a valuable tool in reaching the goal of sustainable food production worldwide. A wide array of nanomaterials has been used to develop strategies of delivery of bioactive compounds aimed at boosting the production and protection of crops. ZnO-NPs, a multifunctional material with distinct properties and their doped counterparts, were widely being studied in different fields of science. However, its application in environmental waste treatment and many other managements, such as remediation, is starting to gain attention due to its low cost and high productivity. Nano-agrochemicals are a combination of nanotechnology with agrochemicals that have resulted in nano-fertilizers, nano-herbicides, nano-fungicides, nano-pesticides, and nano-insecticides being developed. They have anti-bacterial, anti-fungal, anti-inflammatory, antioxidant, and optical capabilities. Green approaches using plants, fungi, bacteria, and algae have been implemented due to the high rate of harmful chemicals and severe situations used in the manufacturing of the NPs. This review summarizes the data on Zn interaction with plants and contributes towards the knowledge of Zn NPs and its impact on plants.

Characteristics and Determinants of the Presence of Respiratory Symptoms among Sewage Workers in Malaysia

Background

The purpose of this study was to determine the relationships of PM 2.5 and H₂S exposure with the presence of work-related respiratory symptoms among sewage workers.

Methods

A cross-sectional study was conducted in eleven sewage plants located in the central region of Peninsular Malaysia. One hundred ninety-one sewage workers were assessed using the British Medical Research Council (BMRC) questionnaire. Area air sampling was performed in three different sewage plants to measure the following parameters: physical air quality and concentration of PM 2.5 and H₂S.

Result

Chronic cough (34.0%) was reported as the most common symptom, followed by chronic phlegm (26.2%), shortness of breath (7.9%), and chest tightness (3.7%). There were five significant determinants of the presence of respiratory symptoms among the sewage workers: shift work (AOR 23.50, 95% CI: 1.90–616.52), working at a sludge treatment facility (STF) (AOR 25.46, 95% CI: 2.06–314.29), a longer duration of working years (AOR 1,21, 95% CI: 1.01–1.44), individual cumulative exposure to PM 2.5 (AOR 9.01, 95% CI: 1.98–83.33), and individual cumulative exposure to H₂S (AOR 1.04, 95% CI: 1.01–1.07). The majority of STF and non-STF workers had higher exposure to PM 2.5 and H₂S concentrations in the air than office workers.

Conclusion

Sewage workers working at non-STFs or STFs reported a significantly higher prevalence of work-related respiratory symptoms and exposure to PM 2.5 and H₂S compared with office workers. Exposure-response relationships were also found in sewage workers' cumulative exposure to PM 2.5 and H₂S and the presence of respiratory symptoms.

Bioremediation and decontamination potentials of metallic nanoparticles loaded nanohybrid matrices - A review

The current nanotechnological advancements provide an astonishing insight to fabricate nanomaterials for nano-bioremediation purposes. Exciting characteristics possessed by hybrid matrices at the nanoscale knock endless opportunities to nano-remediate environmentally-related pollunanomaterials tants of emerging concern. Nanometals are considered among the oldest generation of the world has ever noticed. These tiny nanometals and nanometal oxides showed enormous potential in almost every extent of industrial and biotechnological domains, including their potential multipurpose approach to deal with water impurities. In this manuscript, we discussed their role in the diversity of water treatment technologies used to remove bacteria, viruses, heavy metals, pesticides, and organic impurities, providing an ample perspective on their recent advances in terms of their characteristics, attachment strategies, performance, and their scale-up challenges. Finally, we tried to explore their futuristic contribution to nano-remediate environmentally-related pollutants of emerging concern aiming to collect treated yet safe water that can be reused for multipurpose.

A systematic review on adsorptive removal of hexavalent chromium from aqueous solutions: Recent advances

The contamination of natural resources by hexavalent chromium (Cr(VI)) originating from natural and anthropogenic activities is a serious environmental concern. Although many articles on chromium remediation have been published, a comprehensive understanding of the mechanisms involved in remediation with different sorbents is not yet available. In this systematic review, the performance and applicability of several adsorptive materials for Cr(VI) removal from aqueous media are discussed, along with a detailed analysis of the mechanisms involved. Statistical analysis is applied to compare the efficacies of different adsorbents, while a similar approach is used to determine the effects of sorbent properties and experimental conditions on the adsorption capacity. A detailed analysis of the factors involved in fixed-bed column studies is also presented. A suitable desorption approach to the regeneration of the spent adsorbent and its adsorption performance in reuse is also examined. Among the different sorbents, nanoparticles and mineral-doped biochar were found to be the most effective sorbents, while the adsorption was higher at low pH (~4.0) than that at intermediate pH (6-8). Contrary to our expectation, adsorption was high for sorbents with low specific surface areas, suggesting that the adsorption of Cr(VI) is largely influenced by the chemical properties of the sorbents. The optimum adsorption in fixed-bed column systems is obtained at a lower Cr(VI) ion concentration, a lower influent flow rate, and a higher bed height. Since most of the studies reviewed herein were merely experimental and utilized ideal conditions with the presence of a single contaminant, i.e. Cr(VI) in water, further studies on adsorption dynamics with the presence of other interfering ions are suggested. This review is promising for the further development of Cr(VI) removal strategies and closes the research gaps pertaining to their challenges.

Fluoride ions sorption using functionalized magnetic metal oxides nanocomposites: a review

Fluoride is an anionic pollutant found superfluous in surface or groundwater as a result of anthropogenic actions from improper disposal of industrial effluents. In drinking water, superfluous fluoride has been revealed to trigger severe health problems in humans. Hence, developing a comprehensive wastewater decontamination process for the effective management and preservation of water contaminated with fluoride is desirable, as clean water demand is anticipated to intensify considerably over the upcoming years. In this regard, there have been increased efforts by researchers to create novel magnetic metal oxide nanocomposites which are functionalized for the remediation of wastewater owing to their biocompatibility, cost-effectiveness, relative ease to recover and reuse, non-noxiousness, and ease to separate from solutions using a magnetic field. This review makes an all-inclusive effort to assess the effects of experimental factors on the sorption of fluoride employing magnetic metal oxide nanosorbents. The removal efficiency of fluoride ions onto magnetic metal oxides nanocomposites were largely influenced by the solution pH and ions co-existing with fluoride. Overall, it was noticed from the reviewed researches that the maximum sorption capacity using various metal oxides for fluoride sorption was in the order of aluminium oxides >cerium oxides > iron oxides > magnesium oxides> titanium oxides, and most sorption of fluoride ions was inhibited by the existence of phosphate trailed by sulphate. The mechanism of fluoride sorption onto various sorbents was due to ion exchange, electrostatic attraction, and complexation mechanism.

Bisphenol A Adsorption on Silica Particles Modified with Beta-Cyclodextrins

This study presents the synthesis of silica particles bearing two beta-cyclodextrin (BCD) (beta-cyclodextrin-BCD-OH and diamino butane monosubstituted beta-cyclodextrin-BCD-NH2). The successful synthesis of the BCD-modified silica was confirmed by FT-IR and TGA. Using contact angle measurements, BET analysis and SEM characterization, a possible formation mechanism for the generation of silica particles bearing BCD derivatives on their surface was highlighted. The obtained modified silica displayed the capacity to remove bisphenol A (BPA) from wastewater due to the presence of the BCD moieties on the surface of the silica. The kinetic analysis showed that the adsorption reached equilibrium after 180 min for both materials with qe values of 107 mg BPA/g for SiO2-BCD-OH and 112 mg BPA/g for SiO2-BCD-NH2. The process followed Ho's pseudo-second-order adsorption model sustaining the presence of adsorption sites with different activities. The fitting of the Freundlich isotherm model on the experimental results was also evaluated, confirming the BCD influence on the materials' adsorption properties.

In situ nanoremediation of soils and groundwaters from the nanoparticle's standpoint: A review

Anthropogenic pollution coming from industrial processes, agricultural practices and consumer products, results in the release of toxic substances into rural and urban environments. Once released, these chemicals migrate through the atmosphere and water, and find their way into matrices such as sediments and groundwaters, thus making large areas potentially uninhabitable. Common pollutants, including heavy metal(loid)s, radionuclides, aliphatic hydrocarbons and halogenated organics, are known to adversely affect physiological systems in animal species. Pollution can be cleaned up using techniques such as coagulation, reverse osmosis, oxidation and biological methods, among others. The use of nanoparticles (NPs) extends the range of available technologies and offers particular benefits, not only by degrading, transforming and immobilizing contaminants, but also by reaching inaccessible areas and promoting biotic degradation. The development of NPs is understandably heralded as an environmentally beneficial technology; however, it is only now that the ecological risks associated with their use are being evaluated. This review presents recent developments in the use of engineered NPs for the in situ remediation of two paramount environmental matrices: soils and groundwaters. Emphasis will be placed on (i) the successful applications of nano-objects for environmental cleanup, (ii) the potential safety implications caused by the challenging requirements of [high reactivity toward pollutants] vs. [none reactivity toward biota], with a thorough view on their transport and evolution in the matrix, and (iii) the perspectives on scientific and regulatory challenges. To this end, the most promising nanomaterials will be considered, including nanoscale zerovalent iron, nano-oxides and carbonaceous materials. The purpose of the present review is to give an overview of the development of nanoremediators since they appeared in the 2000s, from their chemical modifications, mechanism of action and environmental behavior to an understanding of the problematics (technical limitations, economic constraints and institutional precautionary approaches) that will drive their future full-scale applications.

A review of recent and emerging antimicrobial nanomaterials in wastewater treatment applications

In this paper, we present a critical review on antimicrobial nanomaterials with demonstrated potential for application as a disinfection technology in wastewater treatment. Studies involving fabrication and testing of antimicrobial nanomaterials for wastewater treatment were gathered, critically reviewed, and analyzed. Our review shows that there are only a few eligible candidate nanoparticles (NPs) (metal and metal oxide) that can adequately serve as an antimicrobial agent. Nanosilver (nAg) was the most studied and moderately understood metal NPs with proven antimicrobial activity followed by ZnO (among antimicrobial metal oxide NPs) which outperformed titania (in the absence of light) in efficacy due to its better solubility in aqueous condition. The direction of future work was found to be in the development of antimicrobial nanocomposites, since they provide more stability for antimicrobial metal and metal oxides NPs in water, thereby increasing their activity. This review will serve as an updated survey, yet touching also the fundamentals of the antimicrobial activity, with vital information for researchers planning to embark on the development of superior antimicrobial nanomaterials for wastewater treatment applications.

Nanoadsorbants for the Removal of Heavy Metals from Contaminated Water: Current Scenario and Future Directions

Heavy metal pollution of aquatic media has grown significantly over the past few decades. Therefore, a number of physical, chemical, biological, and electrochemical technologies are being employed to tackle this problem. However, they possess various inescapable shortcomings curbing their utilization at a commercial scale. In this regard, nanotechnology has provided efficient and cost-effective solutions for the extraction of heavy metals from water. This review will provide a detailed overview on the efficiency and applicability of various adsorbents, i.e., carbon nanotubes, graphene, silica, zero-valent iron, and magnetic nanoparticles for scavenging metallic ions. These nanoparticles exhibit potential to be used in extracting a variety of toxic metals. Recently, nanomaterial-assisted bioelectrochemical removal of heavy metals has also emerged. To that end, various nanoparticle-based electrodes are being developed, offering more efficient, cost-effective, ecofriendly, and sustainable options. In addition, the promising perspectives of nanomaterials in environmental applications are also discussed in this paper and potential directions for future works are suggested.

Current Trends in the Application of Nanomaterials for the Removal of Pollutants from Industrial Wastewater Treatment-A Review

In the recent decades, development of new and innovative technology resulted in a very high amount of effluents. Industrial wastewaters originating from various industries contribute as a major source of water pollution. The pollutants in the wastewater include organic and inorganic pollutants, heavy metals, and non-disintegrating materials. This pollutant poses a severe threat to the environment. Therefore, novel and innovative methods and technologies need to adapt for their removal. Recent years saw nanomaterials as a potential candidate for pollutants removal. Nowadays, a range of cost-effective nanomaterials are available with unique properties. In this context, nano-absorbents are excellent materials. Heavy metal contamination is widespread in underground and surface waters. Recently, various studies focused on the removal of heavy metals. The presented review article here focused on removal of contaminants originated from industrial wastewater utilizing nanomaterials.

Treatment of wastewater from a dairy plant by adsorption using synthesized copper oxide nanoparticles: kinetics and isotherms modeling optimization

Dairy plants produce 1 to 4 L of wastewater per 1 L of processed milk. The wastewater contains high values of chemical oxygen demand (COD) and biochemical oxygen demand (BOD) concentrations, in addition to high levels of dissolved solids. In this study, synthesized copper oxide nanoparticles (CuONPs) coupled with Sophora Japonica fruit, were used as an adsorbent, for the first time, to treat the effluent of dairy plants in a batch adsorption process. The analysis techniques, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were utilized to characterize the adsorbent. The COD removal, using (CuONPs)-based adsorbent, was investigated by varying contact time, masses of the adsorbent, initial COD value and temperatures. The optimum conditions for highest removal percentage were contact time of 120 min, a temperature of 25 °C, pH value of 7.5, and 1 g of adsorbent. The initial COD values used were in the range of 100-700 ppm. The COD percent removal was in the range of 77 to 95%. Freundlich isotherm exhibited the best fitting for the results (R² = 0.998) with a favorable spontaneous exothermic adsorption process. Based on the calculated normalized deviation value, the modified diffusion model, intra-diffusion, and pseudo-second-order kinetics all showed very good fitting for the adsorption data as indicated by the kinetics study.

Nanotechnology in Wastewater Management: A New Paradigm Towards Wastewater Treatment

Clean and safe water is a fundamental human need for multi-faceted development of society and a thriving economy. Brisk rises in populations, expanding industrialization, urbanization and extensive agriculture practices have resulted in the generation of wastewater which have not only made the water dirty or polluted, but also deadly. Millions of people die every year due to diseases communicated through consumption of water contaminated by deleterious pathogens. Although various methods for wastewater treatment have been explored in the last few decades but their use is restrained by many limitations including use of chemicals, formation of disinfection by-products (DBPs), time consumption and expensiveness. Nanotechnology, manipulation of matter at a molecular or an atomic level to craft new structures, devices and systems having superior electronic, optical, magnetic, conductive and mechanical properties, is emerging as a promising technology, which has demonstrated remarkable feats in various fields including wastewater treatment. Nanomaterials encompass a high surface to volume ratio, a high sensitivity and reactivity, a high adsorption capacity, and ease of functionalization which makes them suitable for application in wastewater treatment. In this article we have reviewed the techniques being developed for wastewater treatment using nanotechnology based on adsorption and biosorption, nanofiltration, photocatalysis, disinfection and sensing technology. Furthermore, this review also highlights the fate of the nanomaterials in wastewater treatment as well as risks associated with their use.

Adsorption affinity of Zn (II) ions for nanostructured zirconium phosphate/silica or titania composites

The paper presents the kinetics of Zn (II) ions adsorption as well as its dependence as a function of pH on nanostructured zirconium phosphate and its composites with silica and titania. The nanostructured zirconium phosphate-containing composites were obtained by mechanical processing in the Pulverisette-7 (Fritsch Gmbh) mill. The obtained composites were characterized by a heterogeneous surface coverage of silica gel or titanium oxides. Zinc ions adsorption studies on these adsorbents showed practically complete removal of Zn (II) from aqueous solutions with an initial concentration of < 0.0001 mol/dm3 and a pH > 4 within 10 min.

Kinetic and Isotherm Study of As(III) Removal from Aqueous Solution by PET Track-Etched Membranes Loaded with Copper Microtubes

This paper reports on the synthesis and structure elucidation of track-etched membranes (TeMs) with electrolessly deposited copper microtubes (prepared in etched-only and oxidized polyethylene terephthalate (PET) TeMs), as well as on the comparative testing of arsenic (III) ion removal capacities through bath adsorption experiments. The structure and composition of composites were investigated by X-ray diffraction technique and scanning electron and atomic force microscopies. It was determined that adsorption followed pseudo-second-order kinetics, and the adsorption rate constants were calculated. A comparative study of the applicability of the adsorption models of Langmuir, Freundlich, and Dubinin-Radushkevich was carried out in order to describe the experimental isotherms of the prepared composite TeMs. The constants and parameters of all of the above equations were determined. By comparing the regression coefficients R2, it was shown that the Freundlich model describes the experimental data on the adsorption of arsenic through the studied samples better than others. Free energy of As(III) adsorption on the samples was determined using the Dubinin-Radushkevich isotherm model and was found to be 17.2 and 31.6 kJ/mol for Cu/PET and Cu/Ox_PET samples, respectively. The high EDr value observed for the Cu/Ox_PET composite indicates that the interaction between the adsorbate and the composite is based on chemisorption.

Current and Emerging Adsorbent Technologies for Wastewater Treatment: Trends, Limitations, and Environmental Implications

Wastewater generation and treatment is an ever-increasing concern in the current century due to increased urbanization and industrialization. To tackle the situation of increasing environmental hazards, numerous wastewater treatment approaches are used—i.e., physical, chemical, and biological (primary to tertiary treatment) methods. Various treatment techniques being used have the risks of producing secondary pollutants. The most promising technique is the use of different materials as adsorbents that have a higher efficacy in treating wastewater, with a minimal production of secondary pollutants. Biosorption is a key process that is highly efficient and cost-effective. This method majorly uses the adsorption process/mechanism for toxicant removal from wastewater. This review elaborates the major agricultural and non-agricultural materials-based sorbents that have been used with their possible mechanisms of pollutant removal. Moreover, this creates a better understanding of how the efficacy of these sorbents can be enhanced by modification or treatments with other substances. This review also explains the re-usability and mechanisms of the used adsorbents and/or their disposal in a safe and environmentally friendly way, along with highlighting the major research gaps and potential future research directions. Additionally, the cost benefit ratio of adsorbents is elucidated.

New modeling of 3D quaternary type BaCuZnS-graphene-TiO2 (BCZS-G-T) composite for photosonocatalytic hydrogen evolution with scavenger effect

For the efficient evolution of hydrogen, we designed a 3D quaternary BaCuZnS-graphene-TiO₂ (BCZS-G-T) composite by an ultrasonic method. Herein, we prepared a quaternary material to minimize the bandgap energy and size. We characterized the "as-prepared" composites by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, and electrochemical impedance spectroscopy (EIS). The high hydrogen evolution was attributed to the 3D quaternary BCZS-G-T composite with small bandgap energy because of its high photoelectron recombination properties. In addition, we demonstrated the combination effects with photocatalytic and sonocatalytic treatments with a scavenger. This work highlights the potential application of quaternary graphene-based composites in the field of energy conversion.

Magnetic nanostructures for marine and freshwater toxins removal

Marine and freshwater toxins contaminate water resources, shellfish and aquaculture products, causing a broad range of toxic effects in humans and animals. Different core-shell nanoparticles were tested as a new sorbent for removing marine and freshwater toxins from liquid media. Water solutions were contaminated with 20 μg/L of marine toxins and up to 50 μg/L of freshwater toxins and subsequently treated with 250 or 125 mg/L of nanoparticles. Under these conditions, carbon nanoparticles removed around 70% of saxitoxins, spirolides, and azaspiracids, and up to 38% of diarrheic shellfish poisoning toxins. In the case of freshwater toxins, the 85% of microcystin LR was eliminated; other cyclic peptide toxins were also removed in a high percentage. Marine toxins were adsorbed in the first 5 min of contact, while for freshwater toxins it was necessary 60 min to reach the maximum adsorption. Toxins were recovered by extraction from nanoparticles with different solvents. Gymnodinium catenatum, Prorocentrum lima, and Microcystis aeruginosa cultures were employed to test the ability of nanoparticles to adsorb toxins in a real environment, and the same efficacy to remove toxins was observed in these conditions. These results suggest the possibility of using the nanotechnology in the treatment of contaminated water or in chemical analysis applications.

Removal of aflatoxin B1 from contaminated peanut oils using magnetic attapulgite

The efficient magnetic adsorbent (Fe₃O₄@ATP) was prepared by precipitation through the dispersion of Fe₃O₄ nanoparticles on the natural attapulgite (ATP) and then tested as an adsorbent for aflatoxin B₁ (AFB₁) removal from contaminated oils. The adsorbent characterization results revealed that the Fe₃O₄ were incorporated into the ATP, affording the Fe₃O₄@ATP composite. This magnetic composite displayed a good ability to eliminate AFB₁ from contaminated oils with a removal efficiency of 86.82% using a 0.3% dosage. The Fe₃O₄@ATP possessed paramagnetic character with a saturation magnetization of 50.86 emu/g, enabling its easy separation from the medium using an external magnet. The adsorption process followed the pseudo-second-order model and fitted the Freundlich isotherm well. Moreover, the thermodynamic studies showed that AFB₁ adsorption onto Fe₃O₄@ATP was exothermic and spontaneous. The novelty of this study lies in the fabrication of magnetic composite adsorbents for AFB₁ elimination from oils.

Tunable Molybdenum Disulfide-Enabled Fiber Mats for High-Efficiency Removal of Mercury from Water

The application of molybdenum disulfide (MoS₂) for water decontamination is expanded toward a novel approach for mercury removal using nanofibrous mats coated with MoS₂. A bottom-up synthesis method for growing MoS₂ on carbon nanofibers was employed to maximize the nanocomposite decontamination potential while minimizing the release of the nanomaterial to treated water. First, a co-polymer of polyacrylonitrile and polystyrene was electrospun as nanofibrous mats and pretreated to form pristine carbon fibers. Next, three solvothermal methods of controlled in situ MoS₂ growth of different morphologies were achieved on the surface of the fibers using three different sets of precursors. Finally, these MoS₂-enabled fibers were extensively characterized and evaluated for their mercuric removal efficiency. Two mercury removal mechanisms, including reduction-oxidation reactions and physicochemical adsorption, were elucidated. The two nanocomposites with the fastest (0.436 min^-1 mg^-1) and highest mercury removal (6258.7 mg g^-1) were then further optimized through intercalation with poly(vinylpyrrolidone), which increased the MoS₂ interlayer distance from 0.68 nm to more than 0.90 nm. The final, optimal fabrication technique (evaluated according to mercuric capacity, kinetics, and nanocomposite stability) demonstrated five times higher adsorption than the second-best method and obtained 70% of the theoretical mercury adsorption capacity of MoS₂. Overall, results from this study indicate an alternative, advanced material to increase the efficiency of aqueous mercury removal while also providing the basis for other novel environmental applications such as selective sensing, disinfection, and photocatalysis.

Preparation of Cu nanoparticles fixed on cellulosic walnut shell material and investigation of its antibacterial, antioxidant and anticancer effects

In this study, antibacterial, antioxidant, and anticancer effects of Cu nanoparticles (CuNPs) fixed on cellulosic walnut shell material were investigated. Firstly, three types of walnut shell-supported copper nanoparticles with various sizes (CuNP-WS1 15–22 nm, CuNP-WS2 60–80 nm and, CuNP-WS3 aggregated of metallic nanoparticles) were synthesized. Antibacterial properties of CuNPs were studied on three strains of bacteria; Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes. DPPH (1, 1-Diphenyl-2-picrylhydrazyl) method was used to examining antioxidant properties. Cytotoxic effects of the synthesized nanoparticles on the cancer cell line were studied. Antimicrobial properties of CuNPs showed that these nanomaterials affect both Gram-positive and Gram-negative bacteria. The antioxidant properties of CuNPs increased significantly by increasing the concentration to 10%. CuNPs appeared to have a dose-dependent cytotoxic effect on K562 cells. However, the IC50 of the synthesized nanoparticles against the K562 (25.24 ± 5 μg/mL) cancer cells was lower significantly (P < 0.01) of the IC50 of these compounds against PBMCs (42.54 ± 6.2 μg/mL).