Sustainable Porous Carbon Materials Derived from Wood-Based Biopolymers for CO₂ Capture

Transforming Waste into Wealth: Advanced Carbon-Based Electrodes Derived from Refinery and Coal By-Products for Next-Generation Energy Storage

This comprehensive review addresses the need for sustainable and efficient energy storage technologies against escalating global energy demand and environmental concerns. It explores the innovative utilization of waste materials from oil refineries and coal processing industries as precursors for carbon-based electrodes in next-generation energy storage systems, including batteries and supercapacitors. These waste-derived carbon materials, such as semi-coke, coal gasification fine ash, coal tar pitch, petroleum coke, and petroleum vacuum residue, offer a promising alternative to conventional electrode materials. They present an optimal balance of high carbon content and enhanced electrochemical properties while promoting environmental sustainability through effectively repurposing waste materials from coal and hydrocarbon industries. This review systematically examines recent advancements in fabricating and applying waste-derived carbon-based electrodes. It delves into the methodologies for converting industrial by-products into high-quality carbon electrodes, with a particular emphasis on carbonization and activation processes tailored to enhance the electrochemical performance of the derived materials. Key findings indicate that while higher carbonization temperatures may impede the development of a porous structure, using KOH as an activating agent has proven effective in developing mesoporous structures conducive to ion transport and storage. Moreover, incorporating heteroatom doping (with elements such as sulfur, potassium, and nitrogen) has shown promise in enhancing surface interactions and facilitating the diffusion process through increased availability of active sites, thereby demonstrating the potential for improved storage capabilities. The electrochemical performance of these waste-derived carbon materials is evaluated across various configurations and electrolytes. Challenges and future directions are identified, highlighting the need for a deeper understanding of the microstructural characteristics that influence electrochemical performance and advocating for interdisciplinary research to achieve precise control over material properties. This review contributes to advancing electrode material technology and promotes environmental sustainability by repurposing industrial waste into valuable resources for energy storage. It underscores the potential of waste-derived carbon materials in sustainably meeting global energy storage demands.

Natural Products Derived Porous Carbons for CO2 Capture

As it is now established that global warming and climate change are a reality, international investments are pouring in and rightfully so for climate change mitigation. Carbon capture and separation (CCS) is therefore gaining paramount importance as it is considered one of the powerful solutions for global warming. Sorption on porous materials is a promising alternative to traditional carbon dioxide (CO2 ) capture technologies. Owing to their sustainable availability, economic viability, and important recyclability, natural products-derived porous carbons have emerged as favorable and competitive materials for CO2 sorption. Furthermore, the fabrication of high-quality value-added functional porous carbon-based materials using renewable precursors and waste materials is an environmentally friendly approach. This review provides crucial insights and analyses to enhance the understanding of the application of porous carbons in CO2 capture. Various methods for the synthesis of porous carbon, their structural characterization, and parameters that influence their sorption properties are discussed. The review also delves into the utilization of molecular dynamics (MD), Monte Carlo (MC), density functional theory (DFT), and machine learning techniques for simulating adsorption and validating experimental results. Lastly, the review provides future outlook and research directions for progressing the use of natural products-derived porous carbons for CO2 capture.

Selective Adsorption of Methyl Orange and Methylene Blue by Porous Carbon Material Prepared From Potassium Citrate

As the discharge amount of dye wastewater increases with the development of the textile printing and dyeing industries, the treatment of the dyes in the wastewater becomes more complex. The adsorption method is a commonly used method for treating dye wastewater. The adsorbent is the key factor affecting the adsorption performance. To develop a high-performance adsorbent, a porous carbon material prepared from potassium citrate by the calcination method was applied in the adsorption of dye-containing water in this study. The morphology and pore structure of the porous carbon materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and N2 adsorption/desorption isotherm. The porous carbon material with a specific surface area of 1436 m2 g-1, PC-900, was used as an adsorbent for the adsorption of methyl orange (MO) and methylene blue (MB). The results showed that the maximum adsorption capacity of PC-900 for MO and MB reached 927 and 1853.6 mg g-1, respectively. Studies on adsorption kinetics and adsorption isotherms showed that the pseudo-second-order kinetic model and the Langmuir isotherm model were more appropriate to describe the adsorption process of MO and MB by PC-900. In addition, the results of the mixed adsorption experiment of MO and MB dyes showed that PC-900 had selective adsorption for MB.

Functional Carbon from Nature: Biomass-Derived Carbon Materials and the Recent Progress of Their Applications

Biomass is considered as a promising source to fabricate functional carbon materials for its sustainability, low cost, and high carbon content. Biomass-derived-carbon materials (BCMs) have been a thriving research field. Novel structures, diverse synthesis methods, and versatile applications of BCMs have been reported. However, there has been no recent review of the numerous studies of different aspects of BCMs-related research. Therefore, this paper presents a comprehensive review that summarizes the progress of BCMs related research. Herein, typical types of biomass used to prepare BCMs are introduced. Variable structures of BCMs are summarized as the performance and properties of BCMs are closely related to their structures. Representative synthesis strategies, including both their merits and drawbacks are reviewed comprehensively. Moreover, the influence of synthetic conditions on the structure of as-prepared carbon products is discussed, providing important information for the rational design of the fabrication process of BCMs. Recent progress in versatile applications of BCMs based on their morphologies and physicochemical properties is reported. Finally, the remaining challenges of BCMs, are highlighted. Overall, this review provides a valuable overview of current knowledge and recent progress of BCMs, and it outlines directions for future research development of BCMs.

TiO2@COF Nanowire Arrays: A "Filter Amplifier" Heterojunction Strategy to Reverse the Redox Nature

Surface modification is a promising method to change the surface properties of nanomaterials, but it is limited in enhancing their intrinsic redox nature. In this work, a "filter amplifier" strategy is proposed for the first time to reverse the intrinsic redox nature of materials. This is demonstrated by coating a COF-316 layer with controlled thickness on TiO₂ to form core-sheath nanowire arrays. This unique structure forms a Z-scheme heterojunction to function as "a filter amplifier" which can conceal the intrinsic oxidative sites and increase the extrinsic reductive sites. Consequently, the selective response of TiO₂ is dramatically reversed from reductive ethanol and methanol to oxidative NO₂. Moreover, TiO₂@COF-316 provides remarkably improved sensitivity, response, and recovery speed, as well as unusual anti-humidity properties as compared with TiO₂. This work not only provides a new strategy to rationally modulate the surface chemistry properties of nanomaterials but also opens an avenue to design high-performance electronic devices with a Z-scheme heterojunction.

Low-concentration CO2 capture using metal-organic frameworks - current status and future perspectives

The ever-increasing atmospheric CO₂ level is considered to be the major cause of climate change. Although the move away from fossil fuel-based energy generation to sustainable energy sources would significantly reduce the release of CO₂ into the atmosphere, it will most probably take time to be fully implemented on a global scale. On the other hand, capturing CO₂ from emission sources or directly from the atmosphere are robust approaches that can reduce the atmospheric CO₂ concentration in a relatively short time. Here, we provide a perspective on the recent development of metal-organic framework (MOF)-based solid sorbents that have been investigated for application in CO₂ capture from low-concentration (<10 000 ppm) CO₂ sources. We summarized the different sorbent engineering approaches adopted by researchers, both from the sorbent development and processing viewpoints. We also discuss the immediate challenges of using MOF-based CO₂ sorbents for low-concentration CO₂ capture. MOF-based materials, with tuneable pore properties and tailorable surface chemistry, and ease of handling, certainly deserve continued development into low-cost, efficient CO₂ sorbents for low-concentration CO₂ capture.

Nanotechnology and Wood Science

Nanotechnology, in a sense, is not entirely a new concept [...].

Carbon Dioxide Capture through Physical and Chemical Adsorption Using Porous Carbon Materials: A Review

Due to rapid industrialization and urban development across the globe, the emission of carbon dioxide (CO2) has been significantly increased, resulting in adverse effects on the climate and ecosystems. In this regard, carbon capture and storage (CCS) is considered to be a promising technology in reducing atmospheric CO2 concentration. Among the CO2 capture technologies, adsorption has grabbed significant attention owing to its advantageous characteristics discovered in recent years. Porous carbon-based materials have emerged as one of the most versatile CO2 adsorbents. Numerous research activities have been conducted by synthesizing carbon-based adsorbents using different precursors to investigate their performances towards CCS. Additionally, amine-functionalized carbon-based adsorbents have exhibited remarkable potential for selective capturing of CO2 in the presence of other gases and humidity conditions. The present review describes the CO2 emission sources, health, and environmental impacts of CO2 towards the human beings, options for CCS, and different CO2 separation technologies. Apart from the above, different synthesis routes of carbon-based adsorbents using various precursors have been elucidated. The CO2 adsorption selectivity, capacity, and reusability of the current and applied carbon materials have also been summarized. Furthermore, the critical factors controlling the adsorption performance (e.g., the effect of textural and functional properties) are comprehensively discussed. Finally, the current challenges and future research directions have also been summarized.

Upgrading the value of anaerobic fermentation via renewable chemicals production: A sustainable integration for circular bioeconomy

The single bioprocess approach has certain limitations in terms of process efficiency, product synthesis, and effective resource utilization. Integrated or combined bioprocessing maximizes resource recovery and creates a novel platform to establish sustainable biorefineries. Anaerobic fermentation (AF) is a well-established process for the transformation of organic waste into biogas; conversely, biogas CO₂ separation is a challenging and expensive process. Biological fixation of CO₂ for succinic acid (SA) mitigates CO₂ separation issues and produces commercially important renewable chemicals. Additionally, utilizing digestate rich in volatile fatty acid (VFA) to produce medium-chain fatty acids (MCFAs) creates a novel integrated platform by utilizing residual organic metabolites. The present review encapsulates the advantages and limitations of AF along with biogas CO₂ fixation for SA and digestate rich in VFA utilization for MCFA in a closed-loop approach. Biomethane and biohydrogen processes CO₂ utilization for SA production is cohesively deliberated along with the role of biohydrogen as an alternative reducing agent to augment SA yields. Similarly, MCFA production using VFA as a substrate and functional role of electron donors namely ethanol, lactate, and hydrogen are comprehensively discussed. A road map to establish the fermentative biorefinery approach in the framework of AF integrated sustainable bioprocess development is deliberated along with limitations and factors influencing for techno-economic analysis. The discussed integrated approach significantly contributes to promote the circular bioeconomy by establishing carbon-neutral processes in accord with sustainable development goals.

Facile synthesis of nitrogen-doped porous carbon materials using waste biomass for energy storage applications

A simple, low-cost, and green route for the preparation of lotus carbon (LC) materials using lotus parts including leaves, flowers, fruits (seed pods), and stems as a renewable precursor is reported. Different porous carbons, leaf-carbon (LF-carbon), flower-carbon (FL-carbon), fruit-carbon (FR-carbon), and stem-carbon (ST-carbon) were synthesized from different parts of the lotus plant by simple carbonization method. The as-synthesized LC materials were well-characterized by many techniques such as electron microscopy and spectroscopy techniques, X-ray diffraction, and BET-surface area analysis. These techniques confirmed the porous structure of LC materials and the existence of heteroatoms in the prepared LC materials. The mesoporous structure of LC materials suggested employing it for the supercapacitor applications. The obtained FR-Carbon exhibits a high specific capacitance of 160 F/g in a three-electrode system in an aqueous 1 M H₂SO₄ electrolyte with a high rate performance of 52% retention from 0.5 to 5.0 A/g with good cycling stability of 95%. These results indicate that the porous carbon derived from lotus fruits is a potential electrode material for high-performance supercapacitors.

Pretreatment, modification and applications of sewage sludge-derived biochar for resource recovery- A review

With the quick increase in industrialization and urbanization, a mass of sludge has been produced on the account of increased wastewater treatment facilities. Sewage sludge (SS) management has become one of the most crucial environmental problems because of the existence of various pollutants. However, SS is a carbon-rich material, which has favored novel technologies for biochar production, which can be utilized for dissimilar applications. This review systematically analyzes and summarizes the pretreatment, modification, and especially application of sewage sludge-derived biochar (SSBC), based on published literature. The comparative assessment of pretreatment technology such as pyrolysis, hydrothermal carbonization, combustion, deashing, and co-feeding is presented to appraise their appropriateness for SS resource availability and the production of SSBC. In addition, the authors summarize and analyze the current modification methods and divide them into two categories: physical properties and surface chemical modifications. The applications of SSBC as absorbent, catalyst and catalyst support, electrode materials, gas storage, soil amendment, and sold biofuel are reviewed in detail. Furthermore, the discussion about the existing problems and the direction of future efforts are presented at the end of each section to envisage SS as a promising opportunity for resources rather than a nuisance.

Facile Synthesis of Microporous Carbons from Biomass Waste as High Performance Supports for Dehydrogenation of Formic Acid

Formic acid (FA) is found to be a potential candidate for the storage of hydrogen. For dehydrogenation of FA, the supports of our catalysts were acquired by conducting ZnCl₂ treatment and carbonation for biomass waste. The texture and surface properties significantly affected the size and dispersion of Pd and its interaction with the support so as to cause the superior catalytic performance of catalysts. Microporous carbon obtained by carbonization of ZnCl₂ activated peanut shells (C_PS-ZnCl₂) possessing surface areas of 629 m²·g⁻¹ and a micropore rate of 73.5%. For ZnCl₂ activated melon seed (C_MS-ZnCl₂), the surface area and micropore rate increased to 1081 m²·g⁻¹ and 80.0%, respectively. In addition, the introduction of ZnCl₂ also caused the increase in surface O content and reduced the acidity of the catalyst. The results represented that C_MS-ZnCl₂ with uniform honeycomb morphology displayed the best properties, and the as-prepared Pd/C_MS-ZnCl₂ catalyst afforded 100% hydrogen selectivity as well as excellent catalytic activity with an initial high turnover number (TON) value of 28.3 at 30 °C and 100.1 at 60 °C.

Advances in biopolymer composites and biomaterials for the removal of emerging contaminants

Domestic, agriculture, and industrial activities contaminate the waterbodies by releasing toxic substances and pathogens. Removal of pollutants from wastewater is critical to ensuring the quality of accessible water resources. Several wastewater treatments are often used. Researchers are increasingly focusing on adsorption, ion exchange, electrostatic interactions, biodegradation, flocculation, and membrane filtration for the efficient reduction of pollutants. Biopolymers are a combination of two or more products produced by the living organisms used to give the desired finished product with a unique attribute. Biomaterials are also similar to traditional polymers by having higher flexibility, biodegradability, low toxicity, and nontoxic secondary byproducts producing ability. Grafting, functionalization, and crosslinking will be used to enhance the characteristics of biopolymers. The present chapter will illustrate some of the important biopolymers and its compos that will impact wastewater treatment in the future. Most commonly used biopolymers including chitosan (CS), activated carbon (AC), carbon-nanotubes (CNTs), and graphene oxide (GO) are discussed. Finally, the opportunities and difficulties for applying adsorbents to water pollution treatment are discussed.

Preparation of Nitrogen-Doped Cellulose-Based Porous Carbon and Its Carbon Dioxide Adsorption Properties

Nitrogen-doped cellulose-based porous carbon materials were obtained by hydrothermal method and KOH chemical activation together with melamine as a nitrogen-doping precursor. The effects of hydrothermal temperature on the microstructure and surface morphology of the products were mainly studied. Also, the carbon dioxide adsorption capacity of the prepared porous carbon was investigated. It was found that when the hydrothermal carbonization temperature was 270 °C and the mass ratio of cellulose and melamine was 1:1, the largest micropore specific surface area of 1703 m²·g^-1 and micropore volume of 0.65 cm³·g^-1 were obtained, with a nitrogen-doping composition of 1.68 atom %. At the temperature of 25 °C and under the pressure of 0.1, 0.2, 0.3, and 0.4 MPa, the adsorption amount of CO₂ was 1.56, 3.79, 5.42, and 7.34 mmol·g^-1, respectively. Also, the adsorption process of CO₂ was in good accordance with the Freundlich isotherm model.

"Artificial Wood" Lignocellulosic Membranes: Influence of Kraft Lignin on the Properties and Gas Transport in Tunicate-Based Nanocellulose Composites

Nanocellulose membranes based on tunicate-derived cellulose nanofibers, starch, and ~5% wood-derived lignin were investigated using three different types of lignin. The addition of lignin into cellulose membranes increased the specific surface area (from 5 to ~50 m²/g), however the fine porous geometry of the nanocellulose with characteristic pores below 10 nm in diameter remained similar for all membranes. The permeation of H₂, CO₂, N₂, and O₂ through the membranes was investigated and a characteristic Knudsen diffusion through the membranes was observed at a rate proportional to the inverse of their molecular sizes. Permeability values, however, varied significantly between samples containing different lignins, ranging from several to thousands of barrers (10^-10 cm³ (STP) cm cm^-2 s^-1 cmHg^-1cm), and were related to the observed morphology and lignin distribution inside the membranes. Additionally, the addition of ~5% lignin resulted in a significant increase in tensile strength from 3 GPa to ~6-7 GPa, but did not change thermal properties (glass transition or thermal stability). Overall, the combination of plant-derived lignin as a filler or binder in cellulose-starch composites with a sea-animal derived nanocellulose presents an interesting new approach for the fabrication of membranes from abundant bio-derived materials. Future studies should focus on the optimization of these types of membranes for the selective and fast transport of gases needed for a variety of industrial separation processes.

Activated Carbon/MoO3: Efficient Catalyst for Green Synthesis of Chromeno[d]pyrimidinediones and Xanthenones

BACKGROUND

Nanoscale metal oxide catalysts have been extensively employed in organic reactions because they have been found to influence the chemical and physical properties of bulk material. The chromene (benzopyran) nucleus constitutes the core structure in a major class of many biologically active compounds, and interest in their chemistry consequently continues because of their numerous biological activities. The xanthene (dibenzopyran) derivatives are classified as highly significant compounds which display a number of various bioactive properties. Pyrimidinones have also gained interest due to their remarkable biological utilization, such as antiviral, antibacterial, antihypertensive, antitumor, and calcium blockers effects.

OBJECTIVE

The aim of this work presented herein was to prepare activated carbon/MoO3 nanocomposite and explore its role as a green and recyclable catalyst for the synthesis of chromeno[d]pyrimidinediones and xanthenones under ethanol-drop grinding at room temperature.

METHODS

The activated carbon/MoO3 nanocomposite was prepared successfully via a simple route in which the carbonization of gums as new natural precursors was used for the synthesis of activated carbon. This nanocomposite was then effectively used in a reaction of 3,4-methylenedioxyphenol, aromatic aldehydes, and active methylene compounds, including 1,3-dimethylbarbituric acid and dimedone, to synthesize a series of chromeno[d]pyrimidinediones and xanthenones in high yields. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), Powder x-ray diffractometry (XRD), Scanning electron microscope (SEM), Raman spectroscopy, and also by TGA analysis. Confirmation of the structures of compounds 5(a-g) and 6(a-g) were also established with IR, 1H NMR, and 13C NMR spectroscopic data and also by elemental analyses.

RESULTS

A number of 6,8-dimethyl-10-phenyl-6,10-dihydro-7H-[1,3]dioxolo[4´,5´:6,7]chromeno[2,3- d]pyrimidine-7,9(8H)-diones and 7,7-dimethyl-10-(4-methylphenyl)-6,7,8,10-tetrahydro-9H-[1,3]dioxolo[ 4,5-b]xanthen-9-ones were effectively synthesized using activated carbon/MoO3 nanocomposite (0.05 gr) as a catalyst under ethanol-drop grinding at room temperature. The desired products were obtained in high yields (93-97%) within short reaction times (15-20 min).

CONCLUSION

This paper investigates the catalytic potential of the synthesized activated carbon/MoO3 nanocomposite for the preparation of chromeno[d]pyrimidinediones and xanthenones under the ethanol-drop grinding procedure. The mildness of the reaction conditions, high yields of products, short reaction times, experimental simplicity, and avoiding the use of harmful solvents or reagents makes this procedure preferable for the synthesis of these compounds.

Scientific Attention to Sustainability and SDGs: Meta-Analysis of Academic Papers

Scientific research plays an important role in the achievement of a sustainable society. However, grasping the trends in sustainability research is difficult because studies are not devised and conducted in a top-down manner with Sustainable Development Goals (SDGs). To understand the bottom-up research activities, we analyzed over 300,000 publications concerned with sustainability by using citation network analysis and natural language processing. The results suggest that sustainability science’s diverse and dynamic changes have been occurring over the last few years; several new topics, such as nanocellulose and global health, have begun to attract widespread scientific attention. We further examined the relationship between sustainability research subjects and SDGs and found significant correspondence between the two. Moreover, we extracted SDG topics that were discussed following a convergent approach in academic studies, such as “inclusive society” and “early childhood development”, by observing the convergence of terms in the citation network. These results are valuable for government officials, private companies, and academic researchers, empowering them to understand current academic progress along with research attention devoted to SDGs.

The Potentiality of Rice Husk-Derived Activated Carbon: From Synthesis to Application

Activated carbon (AC) has been extensively utilized as an adsorbent over the past few decades. AC has widespread applications, including the removal of different contaminants from water and wastewater, and it is also being used in capacitors, battery electrodes, catalytic supports, and gas storage materials because of its specific characteristics e.g., high surface area with electrical properties. The production of AC from naturally occurring precursors (e.g., coal, biomass, coconut shell, sugarcane bagasse, and so on) is highly interesting in terms of the material applications in chemistry; however, recently much focus has been placed on the use of agricultural wastes (e.g., rice husk) to produce AC. Rice husk (RH) is an abundant as well as cheap material which can be converted into AC for various applications. Various pollutants such as textile dyes, organic contaminants, inorganic anions, pesticides, and heavy metals can be effectively removed by RH-derived AC. In addition, RH-derived AC has been applied in supercapacitors, electrodes for Li-ion batteries, catalytic support, and energy storage, among other uses. Cost-effective synthesis of AC can be an alternative for AC production. Therefore, this review mainly covers different synthetic routes and applications of AC produced from RH precursors. Different environmental, catalytic, and energy applications have been pinpointed. Furthermore, AC regeneration, desorption, and relevant environmental concerns have also been covered. Future scopes for further research and development activities are also discussed. Overall, it was found that RH-derived AC has great potential for different applications which can be further explored at real scales, i.e., for industrial applications in the future.

Characterization and Modelling Studies of Activated Carbon Produced from Rubber-Seed Shell Using KOH for CO2 Adsorption

Global warming due to the emission of carbon dioxide (CO2) has become a serious problem in recent times. Although diverse methods have been offered, adsorption using activated carbon (AC) from agriculture waste is regarded to be the most applicable one due to numerous advantages. In this paper, the preparation of AC from rubber-seed shell (RSS), an agriculture residue through chemical activation using potassium hydroxide (KOH), was investigated. The prepared AC was characterized by nitrogen adsorption–desorption isotherms measured in Micrometrices ASAP 2020 and FESEM. The optimal activation conditions were found at an impregnation ratio of 1:2 and carbonized at a temperature of 700 °C for 120 min. Sample A6 is found to yield the largest surface area of 1129.68 m2/g with a mesoporous pore diameter of 3.46 nm, respectively. Using the static volumetric technique evaluated at 25 °C and 1.25 bar, the maximum CO2 adsorption capacity is 43.509 cm3/g. The experimental data were analyzed using several isotherm and kinetic models. Owing to the closeness of regression coefficient (R2) to unity, the Freundlich isotherm and pseudo-second kinetic model provide the best fit to the experimental data suggesting that the RSS AC prepared is an attractive source for CO2 adsorption applications.

Synthesis of Porous Organic Polymers with Tunable Amine Loadings for CO2 Capture: Balanced Physisorption and Chemisorption

The cross-coupling reaction of 1,3,5-triethynylbenzene with terephthaloyl chloride gives a novel ynone-linked porous organic polymer. Tethering alkyl amine species on the polymer induces chemisorption of CO₂ as revealed by the studies of ex situ infrared spectroscopy. By tuning the amine loading content on the polymer, relatively high CO₂ adsorption capacities, high CO₂-over-N₂ selectivity, and moderate isosteric heat (Q_st) of adsorption of CO₂ can be achieved. Such amine-modified polymers with balanced physisorption and chemisorption of CO₂ are ideal sorbents for post-combustion capture of CO₂ offering both high separation and high energy efficiencies.

Effect of Air Oxidation on Texture, Surface Properties and Dye Adsorption of Wood-Derived Porous Carbon Materials

Hierarchical porous carbon materials made from cork were fabricated using a facile and green method combined with air activation, without any templates and chemical agents. The influence of air activation on the texture and other surface characteristics of the carbon materials were evaluated by various characterization techniques. Results indicate that air oxidation can effectively improve the surface area and the hierarchical porous structure of carbon materials, as well as increase the number of oxygen-containing functional groups on the carbon surface. The specific surface area and the pore volume of the carbon material activated by air at 450 °C (C800-M450) can reach 580 m²/g and 0.379 cm³/g, respectively. These values are considerably higher than those for the non-activated material (C800, 376 m²/g, 0.201 cm³/g). The contents of the functional groups (C-O, C=O and O-H) increased with rising activation temperature. After air activation, the adsorption capacity of the carbon materials for methylene blue (MB) and methyl orange (MO) was increased from 7.7 and 6.4 mg/g for C800 to 312.5 and 97.1 mg/g for C800-M450, respectively. The excellent dye removal of the materials suggests that the porous carbon obtained from biomass can be potentially used for wastewater treatment.

Nanomaterials and Chemical Modifications for Enhanced Key Wood Properties: A Review

This work briefly reviews the research milestones in the area of wood chemical modification, focusing on acetylated and furfurylated wood which have been scaled up, and exploits the solutions that nanotechnology can offer to wood protection as an alternative green innovative approach in improving key wood properties, namely the dimensional stability when subjected to a fluctuating moisture content and a susceptibility to biodegradability by microorganisms. Recently, nanomaterials were found to be able applicable in wood science. The target is to improve some special physicochemical characteristics of wood in order to resist extreme conditions (climate, bacteria, etc.), giving an enhanced potentiality. It is well-established that the wood cell wall shows a porosity of molecular scale dimensions; this is caused by the partial filling of spaces between the microfibrils of the cellulose mainly by polyoses and lignin. The small-sized nanoparticles can deeply and effectively penetrate into the wood, altering its surface chemistry, improving its properties, and therefore, resulting in a hyper-performance product.