Recent Progress in MOF-Aerogel Fabrication and Applications.

Recent advancements in metal-organic frameworks (MOFs) underscore their significant potential in chemical and materials research, owing to their remarkable properties and diverse structures. Despite challenges like intrinsic brittleness, powdered crystalline nature, and limited stability impeding direct applications, MOF-based aerogels have shown superior performance in various areas, particularly in water treatment and contaminant removal. This review highlights the latest progress in MOF-based aerogels, with a focus on hybrid systems incorporating materials like graphene, carbon nanotube, silica, and cellulose in MOF aerogels, which enhance their functional properties. The manifold advantages of MOF-based aerogels in energy storage, adsorption, and catalysis are discussed, with an emphasizing on their improved stability, processability, and ease of handling. This review aims to unlock the potential of MOF-based aerogels and their real-world applications. Aerogels are expected to reshape the technological landscape of MOFs through enhanced stability, adaptability, and efficiency.

Nursery pigs fed with feed contaminated by aflatoxin B1 (Aspergillus flavus) and anti-mycotoxin blend: Pathogenesis and negative impact on animal health and weight gain.

The present study aimed to evaluate whether a moderate dose of aflatoxin B1 in pigs' diet interferes with pigs' growth and health in the nursery phase and whether an anti-mycotoxin mixture minimizes the adverse effects of the toxin. One blend with Saccharomyces cerevisiae lysate, zeolite, silicon dioxide, propylene glycol, Carduus marianus extract, soy lecithin, and carbonate was used as an anti-mycotoxin. Four treatments, with six repetitions per treatment and three pigs/pen: Afla0-AntiMyc0 - negative control (without aflatoxin); Afla500-AntiMyc0 - positive control (500 ppb of aflatoxin); Afla0-AntiMyc1000 - 1000 mg/kg of anti-mycotoxin blend; Afla500-AntiMyc1000 - 500 ppb aflatoxin +1000 mg/kg of anti-mycotoxin blend. It was observed that pigs in the positive control (Afla500-AntiMyc0) had lower body weight and weight gain when compared to the other treatments during the experimental period. Also, pigs from Afla500-AntiMyc0 had lower feed intake between days 1-20 and 1 to 30 than Afla0-AntiMyc0. The pigs from Afla500-AntiMyc0 had higher levels of liver enzymes aspartate aminotransferase and alanine aminotransferase compared to other treatments. The pigs from Afla500-AntiMyc0 had higher villus height than the other treatments, while the folded size was smaller in this treatment. Crypts were deeper in the intestines of pigs in both treatments that consumed aflatoxin. In general, it is concluded that the intake of aflatoxin B1 by nursery pigs has negative impacts on the health and, consequently, the animals' growth performance; however, the addition of the contaminated feed with an anti-mycotoxin blend was able to protect the pigs, minimizing the adverse effects caused by the mycotoxin.

New Methyl Methacrylate Derived Adsorbents - Synthesis, Characterization and Adsorptive Removal of Toxic Organic Compounds.

This study aimed to synthesize polymeric adsorbents by suspension polymerization using methyl methacrylate (MMA) with different crosslinking monomers. Divinylbenzene (DVB) and aliphatic monomers: ethylene glycol dimethacrylate (EGDMA) or N,N'-methylenebisacrylamide (NN) containing additional amide groups were used. The possibility of using the prepared copolymers (MMA-NN, MMA-EGDMA, MMA-DVB) as adsorbents for the removal of toxic compounds such as dyes (C.I. Acid Red 18 (AR18), C.I. Acid Green 16 (AG16), C.I. Acid Violet 1 (AV1), C.I. Basic Yellow 2 (BY2), C.I. Basic Blue 3 (BB3) and C.I. Basic Red 46 (BR46)) and phenol (PhOH) from dye baths and effluents was evaluated. Preferential adsorption of basic-type dyes compared to acid-type dyes or phenol was observed by the polymers. Adsorbent based on MMA-EGDMA exhibited the highest capacity for investigated dyes and phenol. The pseudo-second order kinetic model as well as the intraparticle diffusion model can find application in predicting sorption kinetics. Based on the equilibrium sorption data fitted to the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich model, uptake of BB3, AV1 and PhOH is rather physisorption than chemisorption. The regeneration yield of MMA-EGDMA does not exceed 60 % using 1 M HCl, 1 M NaCl, and 1 M NaOH in 50 %v/v methanol.

Immobilizing white-rot fungi laccase: Toward bio-derived supports as a circular economy approach in organochlorine removal.

Despite their high persistence in the environment, organochlorines (OC) are widely used in the pharmaceutical industry, in plastics, and in the manufacture of pesticides, among other applications. These compounds and the byproducts of their decomposition deserve attention and efficient proposals for their treatment. Among sustainable alternatives, the use of ligninolytic enzymes (LEs) from fungi stands out, as these molecules can catalyze the transformation of a wide range of pollutants. Among LEs, laccases (Lac) are known for their efficiency as biocatalysts in the conversion of organic pollutants. Their application in biotechnological processes is possible, but the enzymes are often unstable and difficult to recover after use, driving up costs. Immobilization of enzymes on a matrix (support or solid carrier) allows recovery and stabilization of this catalytic capacity. Agricultural residual biomass is a passive environmental asset. Although underestimated and still treated as an undesirable component, residual biomass can be used as a low-cost adsorbent and as a support for the immobilization of enzymes. In this review, the adsorption capacity and immobilization of fungal Lac on supports made from residual biomass, including compounds such as biochar, for the removal of OC compounds are analyzed and compared with the use of synthetic supports. A qualitative and quantitative comparison of the reported results was made. In this context, the use of peanut shells is highlighted in view of the increasing peanut production worldwide. The linkage of methods with circular economy approaches that can be applied in practice is discussed.

Review on magnetic adsorbents for removal of elemental mercury from coal combustion flue gas.

Under the influence of human activities, atmospheric mercury (Hg) concentrations have increased by 450% compared with natural levels. In the context of the Minamata Convention on Mercury, which came into effect in August 2017, it is imperative to strengthen Hg emission controls. Existing Air Pollution Control Devices (APCDs) combined with collaborative control technology can effectively remove Hg2+ and Hgp; however, Hg0 removal is substandard. Compared with the catalytic oxidation method, Hg0 removal through adsorbent injection carries the risk of secondary release and is uneconomical. Magnetic adsorbents exhibit excellent recycling and Hg0 recovery performance and have recently attracted the attention of researchers. This review summarizes the existing magnetic materials for Hg0 adsorption and discusses the removal performances and mechanisms of iron, carbon, mineral-based, and magnetosphere materials. The effects of temperature and different flue gas components, including O2, NO, SO2, H2O, and HCl, on the adsorption performance of Hg0 are also summarized. Finally, different regeneration methods are discussed in detail. Although the research and development of magnetic adsorbents has progressed, significant challenges remain regarding their application. This review provides theoretical guidance for the improvement of existing and development of new magnetic adsorbents.

A novel ZIF-8@IL-MXene/poly (N-isopropylacrylamide) nanocomposite hydrogel toward multifunctional adsorption.

Phenols, dyes, and metal ions present in industrial wastewater can adversely affect the environment and leach biological carcinogens. Given that the current research focuses only on the removal of one or two of those categories. Herein, this work reports a novel ZIF-8@IL-MXene/Poly(N-isopropylacrylamide) (NIPAM) nanocomposite hydrogel that can efficiently and conveniently absorb and separate multiple pollutants from industrial wastewater. Ionic liquid (IL) was grafted onto MXene surfaces using a one-step method, and then incorporated into NIPAM monomer solutions to obtain the IL-MXene/PNIPAM composite hydrogel via in-situ polymerization. ZIF-8@IL-MXene/PNIPAM nanocomposite hydrogels were obtained by in-situ growth of ZIF-8 on the pore walls of composite hydrogels. As-prepared nanocomposite hydrogel showed excellent mechanical properties and can withstand ten repeated compressions without any damage, the specific surface area increased by 100 times, and the maximum adsorption capacities for p-nitrophenol (4-NP), crystal violet (CV), and copper ion (Cu2+) were 198.40, 325.03, and 285.65 mg g-1, respectively, at room temperature. The VPTTs of all hydrogels ranged from 33 to 35 °C, so the desorption process can be achieved in deionized water at 35-40 °C, and its adsorption capacities after five adsorption-desorption cycles decreased to 79%, 91%, and 29% for 4-NP, CV, and Cu2+, respectively. The adsorption data fitting results follow pseudo-second-order kinetics and Freundlich models, which is based on multiple interactions between the functional groups contained in hydrogels and adsorbent molecules. The hydrogel is the first to realize the high-efficiency adsorption of phenols, dyes and metal ions in industrial wastewater simultaneously, and the preparation process of hydrogels is environmentally friendly. Also, giving hydrogel multifunctional adsorption is beneficial to promote the development of multifunctional adsorption materials.

Magnetic biochar as a revolutionizing approach for diverse dye pollutants elimination: A comprehensive review.

The term "biomass" encompasses all substances found in the natural world that were once alive or derived from living organisms or their byproducts. These substances consist of organic molecules containing hydrogen, typically oxygen, frequently nitrogen, and small amounts of heavy, alkaline earth and alkali metals. Magnetic biochar refers to a type of material derived from biomass that has been magnetized typically by adding magnetic components such as magnetic iron oxides to display magnetic properties. These materials are extensively applicable in widespread areas like environmental remediation and catalysis. The magnetic properties of these compounds made them ideal for practical applications through their easy separation from a reaction mixture or environmental sample by applying a magnetic field. With the evolving global strategy focused on protecting the planet and moving towards a circular, cost-effective economy, natural compounds, and biomass have become particularly important in the field of biochemistry. The current research explores a comparative analysis of the versatility and potential of biomass for eliminating dyes as a sustainable, economical, easy, compatible, and biodegradable method. The elimination study focused on the removal of various dyes as pollutants. Various operational parameters which influenced the dye removal process were also discussed. Furthermore, the research explained, in detail, adsorption kinetic models, types of isotherms, and desorption properties of magnetic biochar adsorbents. This comprehensive review offers an advanced framework for the effective use of magnetic biochar, removing dyes from textile wastewater.

Utilizing sludge-based activated carbon for targeted leachate mitigation in wastewater treatment.

Activated carbon (AC) based adsorbents derived from waste sludge were utilized to remediate mixed contaminants in wastewater as an integrated waste-to-resource approach promoting a paradigm shift in management of refuse sludge and wastewater. This review specifically focuses on the remediation of constituents of landfill leachate by sludge-based activated carbon (SBAC). The adsorption effectiveness of SBAC for the exclusion of leachate characters including heavy metals, phenols, dyes, phosphates, and phosphorus were explored with regard to modifiers such as pH, temperature, properties of the adsorbent including functional groups, initial doses of absorbent and adsorbate, and duration of exposure to note the impact of each parameter on the efficiency of adsorption of the sludge adsorbent. Through the works of various researchers, it was noted that the properties of the adsorbent, pH and temperature impact the working of SBACs. The pH of the adsorbent by influencing the functional groups. Temperature was expected to have a paramount effect on the adsorption efficiency of the SBACs. The importance of the regeneration and recycling of the adsorbents as well as their leachability is highlighted. Sludge based activated carbon is recommended as a timely, resource-efficient, and sustainable approach for the remediation of wastewater.

A novel method for production of nitrogen fertilizer with low energy consumption by efficiently adsorbing and separating waste ammonia.

Recovering waste NH3 to be used as a source of nitrogen fertilizer or liquid fuel has recently attracted much attention. Current methods mainly utilize activated carbon or metal-organic frameworks to capture NH3, but are limited due to low NH3 adsorption capacity and high cost, respectively. In this study, novel porous materials that are low cost and easy to synthesize were prepared as NH3 adsorbents by precipitation polymerization with acid optimization. The results showed that adsorption sites (‒COOH, -OH, and lactone) which form chemical adsorption or hydrogen bonds with NH3 were successfully regulated by response surface methods. Correspondingly, the dynamic NH3 adsorption capacity increased from 5.45 mg g-1 to 129 mg g-1, which is higher than most known activated carbon and metal-organic frameworks. Separation performance tests showed that NH3 could also be separated from CO2 and CH4. The findings in this study will advance the industrialization of NH3 polymer adsorbents and provide technical support for the recycling of waste NH3.

Adsorptive removal of heavy metals from aqueous solutions: Progress of adsorbents development and their effectiveness.

Increased levels of heavy metals (HMs) in aquatic environments poses serious health and ecological concerns. Hence, several approaches have been proposed to eliminate/reduce the levels of HMs before the discharge/reuse of HMs-contaminated waters. Adsorption is one of the most attractive processes for water decontamination; however, the efficiency of this process greatly depends on the choice of adsorbent. Therefore, the key aim of this article is to review the progress in the development and application of different classes of conventional and emerging adsorbents for the abatement of HMs from contaminated waters. Adsorbents that are based on activated carbon, natural materials, microbial, clay minerals, layered double hydroxides (LDHs), nano-zerovalent iron (nZVI), graphene, carbon nanotubes (CNTs), metal organic frameworks (MOFs), and zeolitic imidazolate frameworks (ZIFs) are critically reviewed, with more emphasis on the last four adsorbents and their nanocomposites since they have the potential to significantly boost the HMs removal efficiency from contaminated waters. Furthermore, the optimal process conditions to achieve efficient performance are discussed. Additionally, adsorption isotherm, kinetics, thermodynamics, mechanisms, and effects of varying adsorption process parameters have been introduced. Moreover, heavy metal removal driven by other processes such as oxidation, reduction, and precipitation that might concurrently occur in parallel with adsorption have been reviewed. The application of adsorption for the treatment of real wastewater has been also reviewed. Finally, challenges, limitations and potential areas for improvements in the adsorptive removal of HMs from contaminated waters are identified and discussed. Thus, this article serves as a comprehensive reference for the recent developments in the field of adsorptive removal of heavy metals from wastewater. The proposed future research work at the end of this review could help in addressing some of the key limitations facing this technology, and create a platform for boosting the efficiency of the adsorptive removal of heavy metals.

Anti-mycotoxin feed additives: Effects on metabolism, mycotoxin excretion, performance, and total-tract digestibility of dairy cows fed artificially multi-mycotoxin-contaminated diets.

The aim of this study was to evaluate the effects of different anti-mycotoxin feed additives on the concentration of mycotoxins in milk, urine, and blood plasma of dairy cows fed diets artificially contaminated with mycotoxins. Secondarily, performance, total-tract apparent digestibility of nutrients, and blood parameters were evaluated. Twelve multiparous cows (165 ± 45 DIM, 557 ± 49 kg BW, and 32.1 ± 4.57 kg/d milk yield at the start of the experiment) were blocked according to parity, milk yield, and DIM and used in a 4 × 4 Latin square design experiment with 21-d periods, where the last 7 d were used for sampling and data analysis. Treatments were (1) mycotoxin group (MTX), basal diet (BD) without anti-mycotoxin feed additives; (2) hydrated sodium calcium aluminosilicate (HSCA), HSCA added to the BD at 25 g/cow per day; (3) mycotoxin deactivator (MD; Mycofix Plus, dsm-firmenich) added to the BD at 15 g/cow per day (MD15); and (4) MD added to the BD at 30 g/cow per day (MD30). Cows from all treatments were challenged with a blend of mycotoxins containing 404 µg of aflatoxin B1, 5,025 µg of deoxynivalenol (DON), 8,046 µg of fumonisins (FUM), 195 µg of T2 toxin (T2), and 2,034 µg of zearalenone (ZEN) added daily to the BD during the last 7 d of each period. Neither performance (milk yield and composition) nor nutrient digestibility was affected by treatments. All additives reduced aflatoxin M1 (AFM1) concentration in milk, whereas MD15 and MD30 group had lower excretion of AFM1 in milk than HSCA. Deoxynivalenol, FUM, T2, or ZEN were not detected in milk of MD15 and MD30. Concentrations in milk of DON, FUM, T2, and ZEN were similar between MTX and HSCA. Except for AFM1, none of the analyzed mycotoxins were detected in urine of MD30 group. Comparing HSCA to MD treatments, the concentration of AFM1 was greater for HSCA, whereas MD30 was more efficient at reducing AFM1 in urine than MD15. Aflatoxin M1, DON, FUM, and ZEN were not detected in the plasma of cows fed MD30, and DON was also not detected in MD15 group. Plasma concentration of FUM was lower for MD15, similar plasma FUM concentration was reported for HSCA and MTX. Plasma concentration of ZEN was lower for MD15 than MTX and HSCA. Serum concentrations of haptoglobin and hepatic enzymes were not affected by treatments. Blood concentration of sodium was lower in HSCA compared with MD15 and MD30 groups. In conclusion, the mycotoxin deactivator proved to be effective in reducing the secretion of mycotoxins in milk, urine, and blood plasma, regardless of the dosage. This reduction was achieved without adverse effects on milk production or total-tract digestibility in cows fed multi-mycotoxin-contaminated diets over a short-term period. Greater reductions in mycotoxin secretion were observed with full dose of MD.

Ultrafast and highly efficient Cd(II) and Pb(II) removal by magnetic adsorbents derived from gypsum and corncob: Performances and mechanisms.

The utilization of gypsum and biomass in environmental remediation has become a novel approach to promote waste recycling. Generally, raw waste materials exhibit limited adsorption capacity for heavy metal ions (HMIs) and often result in poor solid-liquid separation. In this study, through co-pyrolysis with corncob waste, titanium gypsum (TiG) was transformed into magnetic adsorbents (GCx, where x denotes the proportion of corncob in the gypsum-corncob mixture) for the removal of Cd(II) and Pb(II). GC10, the optimal adsorbent, which was composed primarily of anhydrite, calcium sulfide, and magnetic Fe3O4, exhibited significantly faster adsorption kinetics (rate constant k1 was 218 times and 9 times of raw TiG for Cd(II) and Pb(II)) and higher adsorption capacity (Qe exceeded 200 mg/g for Cd(II) and 400 mg/g for Pb(II)) than raw TiG and previous adsorbents. Cd(II) removal was more profoundly inhibited in a Cd(II) + Pb(II) binary system, suggesting that GC10 showed better selectivity for Pb(II). Moreover, GC10 could be easily separated from purified water for further recovery, due to its high saturation magnetization value (6.3 emu/g). The superior removal capabilities of GC10 were due to adsorption and surface precipitation of metal sulfides and metal sulfates on the adsorbent surface. Overall, these waste-derived magnetic adsorbents provide a novel and sustainable approach to waste recycling and the deep purification of multiple HMIs.

How renal toxins respond to renal function deterioration and oral toxic adsorbent in pH-controlled releasing capsule.

The number of patients with chronic kidney disease (CKD) is increasing. Oral toxin adsorbents may provide some value. Several uremic toxins, including indoxyl sulfate (IS), p-cresol (PCS), acrolein, per- and poly-fluoroalkyl substances (PFAS), and inflammation markers (interleukin 6 [IL-6] and tumor necrosis factor [TNF]-alpha) have been shown to be related to CKD progression. A total of 81 patients taking oral activated charcoal toxin adsorbents (AC-134), which were embedded in capsules that dissolved in the terminal ileum, three times a day for 1 month, were recruited. The renal function, hemoglobulin (Hb), inflammation markers, three PFAS (PFOA, PFOS, and PFNA), and acrolein were quantified. Compared with the baseline, an improved glomerular filtration rate (GFR) and significantly lower acrolein were noted. Furthermore, the CKD stage 4 and 5 group had significantly higher concentrations of IS, PCS, IL-6, and TNF but lower levels of Hb and PFAS compared with the CKD Stage 3 group at baseline and after the intervention. Hb was increased only in the CKD Stage 3 group after the trial (p = .032). Acrolein did not differ between the different CKD stage groups. Patients with improved GFR (responders) (about 77%) and nonresponders had similar baseline GFR. Responders had higher acrolein and PFOA levels throughout the study and a more significant reduction in acrolein, indicating a better digestion function. Both the higher PFOA and lower acrolein may be related to improved eGFR (and possibly to improvements in proteinuria, which we did not measure. Proteinuria is associated with PFAS loss in the urine), AC-134 showed the potential to improve the GFR and decrease acrolein, which might better indicate renal function change. Future studies are needed with longer follow-ups.

Adsorption isotherms and removal of lead (II) and cadmium (II) from aqueous media using nanobiochar and rice husk.

Removal of Cd(II) and Pb(II) from aqueous solutions is a challenging task and the search for novel adsorbents is underway. This study examined the efficiency of nanobiochar (NB) and rice husk (RH) in the adsorption and removal of Cd(II) and Pb(II) from water. The effect of various physicochemical parameters such as initial pH, initial Cd and Pb concentration, adsorbent dosage, and contact time were tested. SEM/EDX images confirmed the adsorption of Pb and Cd with surface physical and chemical changes. The maximum Pb removal was noted at pH 6 using NB (96%) and at pH 8 for RH (90%), and the maximum Cd removal by NB was recorded at 8 pH (91%) and by RH at pH 6 (87%). The decline in adsorption intensity at lower pH suggested protonation of the adsorbent surface causing cation-cation repulsion. Most of the adsorption occurred within the initial 60 min. A continuous gradual increase in the adsorption with time suggested multilayer formation. Of the three isotherms, the Freundlich model fits the present data best, implying an infinite surface coverage and indicating the potential for multilayer adsorption of Pb and Cd on the surfaces of RH and NB adsorbents. In conclusion, this study highlights the promising potential of NB as a cost-effective adsorbent for the removal of Cd and Pb ions from aqueous solutions.

This study explores the effectiveness of utilizing low-cost natural and agricultural waste biomasses for removing Cd(II) and Pb(II) ions from aqueous solutions.

Sequestration of a food dye (sunset yellow) from wastewater using natural adsorbent: a kinetic, isotherm and interference study.

Cocos nucifera, commonly known as coconut is rich in coir dust (CCD) at its outer surface, which is a very significant agri waste used as biosorbent for wastewater treatment. The current work addresses use of CCD for removal of hazardous Sunset Yellow dye (SY) FCF widely used as coloring agent in food industry, from wastewater. The uptake capacity in batch and column mode is 82 mg/g and 160 mg/g respectively. Characterization study including SEM, FTIR and BET results also supported the adsorption process. The comparative analysis with other natural biosorbents showed best results of biosorption with CCD. The output was better at high pH (10) and lower concentration of dye (5 mg/L). The kinetic study suggested pseudo second order rate revealing both adsorbate-adsorbent interdependency. The presence of covalent bonding or valence forces between the interfaces, suggested chemisorption as the rate limiting mechanism with valence forces, hydrogen bonding and pi-pi stacking being the chief forces responsible in binding of the dye molecules to the surface. The isotherm supported Langmuir model with monolayer and uniform adsorption at the interfaces. The interference test confirmed slight decrease in percent adsorption with interference from chloride and sulfate as dominating ions. The techno-economic feasibility highly recommended in field application of the substitute (net profit value, 1.256 Rs/m3, input cost, 0.052 Rs/m3). The industrial sample analysis with lab to land approach justified sustainability and commercial viability of the present work.

Facile removal of a food dye (sunset yellow, FCF) using Coconut coir dust (CCD).Uptake capacity in batch and column mode is 82 mg/g and 160 mg/g respectively.Chemisorption as the rate limiting mechanism with valence forces, hydrogen bonding and pi-pi stacking being the chief forces.Better uptake efficiency is seen at higher pH (10) and lower concentration (5mg/L).

Recycling of Sewage Sludge: Synthesis and Application of Sludge-Based Activated Carbon in the Efficient Removal of Cadmium (II) and Lead (II) from Wastewater.

The limited supply of drinking water has aroused people's curiosity in recent decades. Adsorption is a popular method for removing hazardous substances from wastewater, especially heavy metals, as it is cheap, highly efficient, and easy to use. In this work, a new sludge-based activated carbon adsorbent (thickened samples SBAC1 and un-thickened samples SBAC2) was developed to remove hazardous metals such as cadmium (Cd+2) and lead (Pb+2) from an aqueous solution. The chemical structure and surface morphology of the produced SBAC1 and SBAC2 were investigated using a range of analytical tools such as CHNS, BET, FT-IR, XRD, XRF, SEM, TEM, N2 adsorption/desorption isothermal, and zeta potential. BET surface areas were examined and SBAC2 was found to have a larger BET surface area (498.386 m2/g) than SBAC1 (336.339 m2/g). While the average pore size was 10-100 nm for SBAC1 and 45-50 nm for SBAC2. SBAC1 and SBAC2 eliminated approximately 99.99% of Cd+2 and Pb+2 out the water under all conditions tested. The results of the adsorption of Cd+2 and Pb+2 were in good agreement with the pseudo-second-order equation (R2 = 1.00). Under the experimental conditions, the Cd+2 and Pb+2 adsorption equilibrium data were effectively linked to the Langmuir and Freundlich equations for SBAC1 and SBAC2, respectively. The regeneration showed a high recyclability for the fabricated SBAC1 and SBAC2 during five consecutive reuse cycles. As a result, the produced SBAC1 and SBAC2 are attractive adsorbents for the elimination of heavy metals from various environmental and industrial wastewater samples.

Chitosan-Based Beads Incorporating Inorganic-Organic Composites for Copper Ion Retention in Aqueous Solutions.

In recent years, there has been a challenging interest in developing low-cost biopolymeric materials for wastewater treatment. In the present work, new adsorbents, based on different types of chitosan (commercial, commercial chitin-derived chitosan and chitosan synthesized from shrimp shell waste) and inorganic-organic composites have been evaluated for copper ions removal. The efficacy of the synthesis of chitosan-based composite beads has been determined by studying various characteristics using several techniques, including FTIR spectroscopy, X-ray diffraction, porosimetry (N2 adsorption), and scanning electron microscopy (SEM). Adsorption kinetics was performed using different adsorption models to determine the adsorption behavior of the materials in the aqueous media. For all composite beads, regardless of the type of chitosan used, good capacity to remove copper ions from simulated waters was observed (up to 17 mg/g), which proves that the new materials hold potential for heavy metal retention. However, the adsorption efficiency was influenced by the type of chitosan used. Thus, for the series where commercial chitosan (CC) was used, the removal efficiency was approximately 29%; for the series with chitosan obtained from commercial chitin (SC), the removal efficiency was approximately 34%; for the series with chitosan enriched with CaCO3 (SH), the removal efficiency was approximately 52%.

A cutting-edge approach to remove arsenic contents from ground water via sulfur doped copper ferrites (S-CuFe2O4) †.

Pure water is necessary for healthy life; however natural ground water has many toxic metals. Before drinking, it must be free from toxic metals that commonly causes cancer. For example, arsenic is hazardous element but unfortunately it is naturally present in ground water. Due to its high solubility, removal of arsenic from water is not easy. In recent decades, presence of arsenic in ground water has been reported in many areas of Pakistan. Purpose of current project is to estimate and eliminate arsenic contents from the ground drinking water of Tribal Belt of DG Khan. For the comprehensive survey, 200 water samples were collected from the areas where large proportion of ground water is being consumed for drinking. In this work, relatively cheaper and effective adsorbent namely S‒CuFe2O4 have been synthesized for the quick removal of arsenic. Arsenic contents were converted to the arsenomolybdate complex (AMC) and this complex was then adsorbed on S‒CuFe2O4. Morphology and chemical characteristics have been evaluated via XRD, SEM, FT-IR, Raman, TGA, EDX, AFM and XPS techniques. Additionally, various kinetic models were employed to confirm and validate the adsorption phenomena. Based on the results and assessment, it has been concluded that 1.5 g of aforementioned adsorbent is adequate to deliver 432 gal of arsenic free water.

Adaptable strategy for reactivation and recycling of spent S-Zorb adsorbents at the laboratory and pilot scale.

The spent S-Zorb adsorbents containing Ni and Zn elements are hazardous wastes. It would generate significant economic and environmental benefits to reactivate and recycle these solid wastes through a reactivation strategy. Furthermore, adaptability investigation of this strategy is also indispensable before its industrial application. Herein, the spent S-Zorb adsorbents (Spent-TJ/MM/QD) from different plants were reactivated at laboratory and pilot scale in 3 m3 reactor via an acid-base coupling reactivation strategy. The spent adsorbents exhibit distinct phase compositions and microstructures of active components. Formation of ZnSi2O4 and ZnS is the primary reason for abandonment of the Spent-TJ (Spent-MM) and Spent-QD, respectively. The nickel species also exhibit different aggregation extent. Fortunately, the inert zinc and nickel species are respectively converted into ZnO and NiO during the reactivation process. Higher surface area (1.7-4.0 times that of the spent adsorbents) and more acid sites are generated over the reactivated adsorbents. Besides, all the reactivated adsorbents possess similar phase compositions and microstructures. Both the adsorbents reactivated at pilot and laboratory scale exhibit comparable desulfurization activity to fresh ones. The sulfur content of the gasoline desulfurized by the reactivated adsorbents is below 10 µg g-1, meeting the Euro V legislations. All the results indicate the excellent adaptability and commercial potential of the reactivation strategy. The possible mechanism for the excellent adaptability of the reactivation method was proposed.

Facile synthesis of eco-friendly alginate-chitosan bio-adsorbent for critical raw materials adsorption: A comprehensive study.

Sustainable management of critical raw materials is of paramount importance to ensure a steady supply and reduce environmental impact. The application of newly synthesized and environmentally friendly ALG@CS material as a bio-adsorbent for the effective rare earth elements removal from aqueous solution has been presented. The synthesized material underwent FTIR, XPS, EDX, and SEM analysis to determine its suitability for metal uptake. To evaluate the adsorption capacity of ALG@CS for rare earth elements several factors were taken into consideration. These factors included alginate:chitosan ratios, bead size, pH level, composite mass, interaction time, metal ion concentration, and temperature, being all varied during the batch mode evaluation process. Under the optimal conditions, the maximum adsorption capacities were found to be 145.90 mg La(III)/g, 168.44 mg Ce(III)/g, 132.51 mg Pr(III)/g, 128.40 mg Nd(III)/g, 154.36 mg Sm(III)/g, and 165.10 mg Ho(III)/g. The equilibrium data fits well with non-linear three-parameter Sips and Redlich-Peterson isotherm models. The PSO model finds the highest process suitability. The synthesized ALG@CS bio-adsorbent showed excellent regenerative capacity in ten cycles, making it a suitable adsorbent for rare earth elements uptake. The unique bio-adsorbents combination allows for efficient critical raw materials adsorption providing a promising solution for their recovery and recycling.