Application of experimental design for removal of sunset yellow by copper sulfide nanoparticles loaded on activated carbon

Quaternary ammonium-modified cellulose: A sustainable strategy for purifying aqueous solutions contaminated with sunset yellow dye

This study showcases the remarkable efficacy of quaternary ammonium-modified cellulose as a highly sustainable biosorbent for removing Sunset Yellow (SY) dye from water. Detailed analysis was conducted using infrared (FTIR) spectroscopy for structural changes and Scanning Electron Microscopy (SEM) for morphological changes. A minimal yet highly effective dose of 0.05 g was identified through dedicated optimization experiments, achieving near-complete removal (99 %) of SY. The biosorbent demonstrated exceptional performance across a broad pH range (2-10), accomplishing remarkable removal within just 5 min. Langmuir modeling uncovered a monolayer sorption mechanism with a high maximum capacity (107.08 mg g-1), and thermodynamic analysis affirmed the spontaneity and favorability of the sorption process. Noteworthy is the biosorbent's impressive regeneration capabilities (up to 95 %) using 1.0 M NaOH or HCl solutions and its sustained performance over three sorption-regeneration cycles, highlighting its exceptional stability and reusability. The modified cellulose exhibited remarkable resistance to common interfering ions (chloride, nitrate, and sulfate) at 10 and 100 mg L-1 concentrations. These combined features position quaternary ammonium-modified cellulose as a promising, sustainable, and efficient option for dye wastewater treatment.

Adsorption of Malachite Green by extracellular polymeric substance of Lysinibacillus sp. SS1: kinetics and isotherms

Use of novel biological materials as adsorbents for removal of xenobiotics is gaining significance owing to their exceptional advantages. An extracellular polymeric substance (EPS) produced by Lysinibacillus sp. SS1 had rough porous surface as observed by SEM analysis. Adsorption ability of EPS was estimated against various textile dyes such as Malachite Green (MG), Methyl Orange, Congo Red and Coomassie Blue. About 82% of MG (100 mg/L) was adsorbed onto 2.5 mg EPS within 30 min. Effect of MG concentration, EPS weight, agitation speed and incubation time on adsorption, studied by one factor at a time approach, revealed that adsorption was influenced by all factors. Maximum adsorption of 99.01 ± 0.61% was achieved at 100 mg/L MG, 10 mg EPS, 120 RPM in 75 min with maximum adsorption capacity of 247.5 mg/g. Kinetics was affected by MG and EPS amounts, with shift from pseudo first to pseudo second order with increase in concentration. Adsorption of MG by EPS of Lysinibacillus sp. SS1 was identified as unilayer chemisorption as it followed Langmuir isotherm with maximum adsorption capacity (Q _m ) of 178.57 mg/g (R ² = 0.9889). This is the first report on potential of EPS produced by Lysinibacillus sp. SS1 as novel biodegradable adsorbent with high efficacy of MG removal from aqueous solutions.

Application of response surface methodology in physicochemical removal of dyes from wastewater: A critical review

Response surface methodology (RSM) is a powerful tool in designing the experiments and optimizing different environmental processes. However, when it comes to wastewater treatment and specifically dye-containing wastewater, two questions arise; "Is RSM being used correctly?" and "Are all capabilities of RSM being exploited properly?". The current review paper aims to answer these questions by scrutinizing different physicochemical processes that utilized RSM in dye removal. The literature that applied RSM to adsorption, advanced oxidation processes, coagulation/flocculation and electrocoagulation processes were critically reviewed in this paper. The common errors in applying RSM to physicochemical removal of dyes are identified and some suggestions are made for future studies.

Compound Copper Chalcogenide Nanocrystals

This review captures the synthesis, assembly, properties, and applications of copper chalcogenide NCs, which have achieved significant research interest in the last decade due to their compositional and structural versatility. The outstanding functional properties of these materials stems from the relationship between their band structure and defect concentration, including charge carrier concentration and electronic conductivity character, which consequently affects their optoelectronic, optical, and plasmonic properties. This, combined with several metastable crystal phases and stoichiometries and the low energy of formation of defects, makes the reproducible synthesis of these materials, with tunable parameters, remarkable. Further to this, the review captures the progress of the hierarchical assembly of these NCs, which bridges the link between their discrete and collective properties. Their ubiquitous application set has cross-cut energy conversion (photovoltaics, photocatalysis, thermoelectrics), energy storage (lithium-ion batteries, hydrogen generation), emissive materials (plasmonics, LEDs, biolabelling), sensors (electrochemical, biochemical), biomedical devices (magnetic resonance imaging, X-ray computer tomography), and medical therapies (photochemothermal therapies, immunotherapy, radiotherapy, and drug delivery). The confluence of advances in the synthesis, assembly, and application of these NCs in the past decade has the potential to significantly impact society, both economically and environmentally.

Comparative study on ultrasonic assisted adsorption of dyes from single system onto Fe3O4 magnetite nanoparticles loaded on activated carbon: Experimental design methodology

The present study the ultrasound assisted adsorption of dyes in single system onto Fe₃O₄ magnetite nanoparticles loaded on activated carbon (Fe₃O₄-MNPs-AC) was described following characterization and identification of this adsorbent by conventional techniques likes field emission scanning electron microscopy, transmission electron microscopy, particle-size distribution, X-ray diffraction and Fourier transform infrared spectroscopy. A central composite design in conjunction with a response surface methodology according to f-test and t-test for recognition and judgment about significant term led to construction of quadratic model which represent relation among responses and effective terms. This model has unique ability to predict adsorption data behavior over a large space around central and optimum point. Accordingly Optimum conditions for well and quantitative removal of present dyes was obtained best operation and conditions: initial SY, MB and EB dyes concentration of 15, 15 and 25mgL^-1, 4.0, 6.0 and 5.0 of pH, 360, 360 and 240s sonication time and 0.04, 0.03 and 0.032g of Fe₃O₄-MNPs-AC. Replication of similar experiment (N=5) guide that average removal percentage of SY, MB and EB were found to be 96.63±2.86%, 98.12±1.67% and 99.65±1.21% respectively. Good agreement and closeness of Predicted and experimental result and high adsorption capacity of dyes in short time strongly confirm high suitability of present method for waste water treatment, while easy separation of present nanoparticle and its good regeneration all support good applicability of Fe₃O₄-MNPs-AC for waste water treatment. The kinetic study can be represented by combination of pseudo second-order and intraparticle diffusion. The obtained maximum adsorption capacities correspond to Langmuir as best model for representation of experimental data correspond to dyes adsorption onto Fe₃O₄-MNPs-AC were 76.37, 78.76 and 102.00mgg^-1 for SY, MB and EB, respectively. In addition, the performance comparison of ultrasound-assisted, magnetic stirrer assisted and vortex assisted adsorption methods demonstrates that ultrasound is an effective and good choice for facilitation of adsorption process via. Compromise of simple and facile diffusion.

Removal of sunset yellow FCF from aqueous solution using polyethyleneimine-modified MWCNTs

A novel adsorbent consisting of polyethyleneimine-modified multi-wall carbon nanotubes (PEI-MWCNTs) was synthesized by grafting PEI on the carboxyl MWCNTs. The surface properties of the PEI-MWCNTs were measured by scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared, and zeta potential. The adsorption behavior of the PEI-MWCNTs was investigated using sunset yellow FCF as adsorbate. The effects of dosage of adsorbent, the initial pH of solution, contact time and temperature on the adsorption capacity were studied. Then, the kinetics and thermodynamics of the adsorption process were further investigated. Experimental results showed that the adsorption kinetics fitted a pseudo-second-order model and the adsorption isotherms agreed well with the Langmuir model. The adsorption process occurred very fast and the adsorption capacity of PEI-MWCNTs was much higher than that of many of the previously reported adsorbents. Additionally, the plausible adsorption mechanism was discussed.

Random forest model for the ultrasonic-assisted removal of chrysoidine G by copper sulfide nanoparticles loaded on activated carbon; response surface methodology approach

Copper sulfide nanoparticle-loaded activated carbon (CuS-NP-AC) was prepared and used as an adsorbent for the accelerated removal of chrysoidine G (CG) assisted by ultrasound.

Adsorption of protein onto double layer mixed matrix membranes

This work proposed a novel approach for protein purification by using double layer mixed matrix membranes (MMMs). The double layer MMMs consisting of an active support and separating layer were prepared by co-casting two polymer solutions onto a glass plate. The active support layer consisted of nano hydroxyapatite (HAP) particles embedded in macroporous polyether sulfone (PES) and the separating layer was particle free PES membrane. The influence of separating layer with different PES content on membrane morphology was studied. The double layer MMMs were further characterized concerning permeability and adsorption capacity. The double layer MMMs showed purification of protein via diffusion as well as adsorption. The bovine serum albumin (BSA) was used as a model protein. The properties and structures of double layer MMMs prepared by immersion phase separation process were characterized by pure water flux, BSA adsorption and scanning electron microscopy (SEM).