Decontamination Of Materials Research Articles

Effective decontamination of DR-81 dye from aqueous solutions using eco-friendly graphene oxide nanoparticles.

Effective management of industrial and agricultural wastes requires a multifaceted approach that considers environmental, economic, and social factors. Our ability to recover resources and create a circular bioeconomy from agricultural waste can be enhanced by implementing sustainable methods such as reducing, reusing, and recycling it. Active graphene oxide (GO) was prepared through the gasification of agricultural waste and further mixed with FeAlOx catalyst for three hours at 800°C as an efficient adsorbent. The synthesized material was comprehensively characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller surface area analysis, and thermal gravimetrical analysis. In order to remove direct red 81 (DR-81) dye from wastewater, the synthesized nanomaterial was implemented as an effective adsorbent. Several processing variables, including pH, contact time, and dosage, were studied to examine the optimum conditions that directly influence the DR-81 decontamination of onto the fabricated GO. The optimal dosage from the synthesized GO for DR-81 decontamination was 0.5g/L at pH = 7 after 30min. At pH 7.0 and 25°C, the produced GO had the highest sorption capacity of 132.14mg/g towards the DR-81. In addition, equilibrium and kinetic studies were capably fitted via the Freundlich and pseudo-second-order models, respectively. As a result of its particular properties, which include a high surface area, adsorption capacity, structural robustness, variation tolerance, and thermal stability. These promising findings supported the usage of synthesized GO as a superior adsorbent material for DR-81 decontamination from wastewater.

Synthesis and characterization of halloysite-cerium nanocomposite for removal of manganese

This study explores the use of a Halloysite composite to efficiently remove manganese from water through adsorption. We optimized experimental parameters, such as dosage (3 g/L), contact time, pH levels (ranging from 2 to 12), and initial Mn concentration (20 ppm), first in distilled water and then in polluted water. The main objective is to create an environmentally friendly material for practical manganese removal, especially important for at-risk populations like young individuals exposed to manganese. Using an oxidation-reduction approach, we synthesized a Halloysite-mediated nanocomposite for manganese removal through adsorption. The composite's crystallinity increased from 70.88 % to 77.4 % after manganese adsorption, indicating successful adsorption. At a transition temperature of 303 K, the composite showed an impressive 93 % manganese removal efficiency. We conducted comprehensive analyses using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Transmission Electron Microscope (TEM), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), and UV–visible spectrophotometry to compare the composite's performance before and after adsorption. These results provide valuable insights into the structural changes and performance characteristics of the synthesized composite in manganese removal. Optimized experimental parameters and methodology lay the groundwork for further exploration of eco-friendly materials for water decontamination.

Ambidextrous approach in action: Mg(OMe)2-doped hierarchical porous zirconium MOFs for decontaminating toxic chemical agents in nonbuffered systems

Utilizing a ligand-truncation strategy, a hierarchically porous structure was engineered within MOF-808, designated as HP-MOF-808. Furthermore, Mg(OMe)2 doping yielded HP-MOF-808@Mg(OMe)2, materials with both hierarchical porosity and basic character, for decontamination of two types of toxic chemical agents in nonbuffered solutions. In aqueous solution, the HP-808-2 exhibited decontamination rate constants for dimethyl-4-nitrophenyl phosphate (DMNP) and the nerve agent soman (GD) that were 3.13 and 1.98 times higher than MOF-808, respectively. The decontamination half-lives of HP-808-2@Mg(OMe)2 1:2 for DMNP and GD were further reduced by 13.87 and 36.82 times compared to HP-808-2. The material retains its decontamination efficacy for DMNP even after 60-days exposure in air and maintains structural integrity in solvents devoid of labile hydrogen for at least 24 h. In methanol, HP-808-2@Mg(OMe)2 achieved 100% DMNP decontamination in 25 min, outperforming HP-808-2 at 31.8%, marking it as the fastest DMNP decontamination material in methanol. Theoretical simulations confirmed the experimental findings, clearly demonstrating the energy changes during reactions with various nucleophiles and revealing the degradation process and mechanism of DMNP on the active sites of MOFs. Moreover, these materials rapidly degraded 2-chloroethyl ethyl sulfide (CEES) through hydrolysis, dehydrohalogenation, and heterolytic cleavage, demonstrating great potential for dual decontamination of toxic chemical agents in unbuffered systems.

Harnessing perovskite materials for water decontamination: a comprehensive review.

Perovskites have recently emerged as a promising class of materials with a wide range of applications, including solar cells, light-emitting diodes, and catalysts. In addition, perovskites have demonstrated significant potential for water decontamination due to their tunable properties and facile synthesis. This review article provides a comprehensive overview of perovskites, including their preparation techniques, crystal structure, and electronic properties. The article also highlights the various applications of perovskites, with a particular focus on their use in water decontamination. The different types of perovskites for water decontamination, including simple, substituted, and doped perovskites, as well as nanoscopic and supported perovskites, are discussed in detail. Furthermore, the article addresses the beneficial costs of perovskites and the environmental impacts associated with their use, including toxicity and end-of-life management. The aim of this review article is to provide a broad perspective on perovskites and their potential for water decontamination, as well as future prospects and challenges in various applications.

Synthetic Zeolite from Blast Furnace Slag (BFS) as an effective sorbent for simultaneous removal of Cadmium and Copper ions

The main challenge for remediation of metals contaminated water is the application of a proper, effective, low-cost material for decontamination of hazardous metal. In this study, low-cost zeolite derived from blast furnace slag (Z-BFS) by a facile hydrothermal method was investigated for adsorption of copper (Cu2+) and cadmium (Cd2+) ions from aqueous solutions. Furthermore, the characteristics of the prepared Z-BFS were evaluated via different techniques (FT-IR, XRF, XRD, SEM and EDX). The results showed the complete removal of Cd2+ and Cu2+ ions. Notably, the maximum adsorption capacity of metals had the trend Cu2+ (103 mg/g) > Cd2+ (80 mg/g) within 20 min at pH 5.5 and 2 g Z-BFS/l. The experimental data fit well with the pseudo-second order kinetic model elucidating that chemisorption is the rate determining step. The isotherms of adsorption were satisfactorily described by the Langmuir isotherm model indicating the monolayer adsorption process. The thermodynamic study demonstrated that adsorption process is endothermic. The obtained results from this study show that Z-BFS proves to be a proper candidate adsorbent for the removal of Cd2+ and Cu2+ ions from contaminated water.

New Insights into Materials for Pesticide and Other Agricultural Pollutant Remediation.

The increase in the world population and the intensification of agricultural practices have resulted in the release of several contaminants into the environment, especially pesticides and heavy metals. This article reviews recent advances in using adsorbent and catalytic materials for environmental decontamination. Different materials, including clays, carbonaceous, metallic, polymeric, and hybrid materials, are evaluated for their effectiveness in pollutant removal. Adsorption is an effective technique due to its low cost, operational simplicity, and possibility of adsorbent regeneration. Catalytic processes, especially those using metallic nanoparticles, offer high efficiency in degrading complex pesticides. Combining these technologies can enhance the efficiency of remediation processes, promoting a more sustainable and practical approach to mitigate the impacts of pesticides and other agricultural pollutants on the environment. Therefore, this review article aims to present several types of materials used as adsorbents and catalysts for decontaminating ecosystems affected by agricultural pollutants. It discusses recent works in literature and future perspectives on using these materials in environmental remediation. Additionally, it explores the possibilities of using green chemistry principles in producing sustainable materials and using agro-industrial waste as precursors of new materials to remove contaminants from the environment.

Performance of removing aqueous contaminant by zirconium based adsorbents: a critical review

The studies on materials for decontamination in aqueous solutions have increasingly received greater attentions. Such contaminants as heavy metals, arsenic, fluoride and phosphate are harmful to humans and aqueous species due to higher toxicity. Zirconium based adsorbents have become more attractive due to outstanding performance in decontamination. This article provides a comprehensive review of the performance and mechanisms of five types adsorbents: zirconium (hydro)oxides, zirconium hydrogen sulfate, zirconium based multiple metal typed adsorbents and zirconium impregnated complexes. The pseudo-first order and pseudo-second order equations and the intraparticle diffusion model can be applied in describing the adsorption kinetics, while Langmuir and Freundlich equations are the most commonly used adsorption isotherms. The important mechanisms for uptake of contaminants are: ligand exchange between adsorbate and adsorbent, surface complexation formation, and Lewis acid–base and electrostatic interactions. A series of successful studies demonstrate that the adsorbents are promising for removing aqueous contaminants.

Support Platform of Functionalized Sustainable Cellulose Self-Entanglement Monolithic Adsorbents for Efficient Adsorption of Cadmium(II) Ions.

Serious water contamination induced by massive discharge of cadmium(II) ions is becoming an emergent environmental issue due to high toxicity and bioaccumulation; thus, it is extremely urgent to develop functional materials for effectively treating with Cd2+ from wastewater. Benefiting from abundant binding sites, simple preparation process, and adjustable structure, UiO-66-type metal-organic frameworks (MOFs) had emerged as promising candidates in heavy metal adsorption. Herein, monolithic UiO-66-(COOH)2-functionalized cellulose fiber (UCLF) adsorbents were simply fabricated by incorporating MOFs into cellulose membranes through physical blending and self-entanglement. A two-dimensional structure was facilely constructed by cellulose fibers from sustainable biomass agricultural waste, providing a support platform for the integration of eco-friendly UiO-66-(COOH)2 synthesized with lower temperature and toxicity solvent. Structure characterization and bath experiments were performed to determine operational conditions for the maximization of adsorption capacity, thereby bringing out an excellent adsorption capacity of 96.10 mg/g. UCLF adsorbent holding 10 wt % loadings of UiO-66-(COOH)2 (UCLF-2) exhibited higher adsorption capacity toward Cd2+ as compared to other related adsorbents. Based on kinetics, isotherms, and thermodynamics, the adsorption behavior was spontaneous, exothermic, as well as monolayer chemisorption. Coordination and electrostatic attraction were perhaps mechanisms involved in the adsorption process, deeply unveiled by the effects of adsorbate solution pH and X-ray photoelectron spectroscopy. Moreover, UCLF-2 adsorbent with good mechanical strength offered a structural guarantee for the successful implementation of practical applications. This study manifested the feasibility of UCLF adsorbents used for Cd2+ adsorption and unveiled a novel strategy to shape MOF materials for wastewater decontamination.

Nanocomposite materials for decontamination of highly toxic acid dye from aqueous streams

ABSTRACT The rising issue of water pollution, driven by industry, urbanisation, and population increase, needs urgent action to address the release of contaminants. This study tackles the critical need for a low-cost, highly efficient adsorbent to extract toxic dyes from aqueous streams. The innovation lies in the synthesis of Cu/TiO2-CWSP composite, and composites with varying percentages of copper doping and comparing Cu/TiO2-CWSP composites with other nanocomposites, such as Li/TiO2-CWSP, Na₂SiO₃-CWSP, and various CaO-Fe-based composites. The works thoroughly optimised important parameters, including adsorbent dosage, pH, initial dye concentration, and exposure period, demonstrating their major influence on dye removal efficiency. Furthermore, the study assessed the effect of beginning pH on the adjustment of final pH, demonstrating variable efficiency levels depending on initial conditions. Recent research has evaluated numerous adsorbents, analysed by SEM. The highest % removal of acid green dye using Cu/TiO2-CWSP composite was at pH 7, dose of 0.5 g/L with a value of 99.12% achieved after 60 minutes only. The removal effectiveness of acid green dye improved as the percentage of Cu/TiO2 in the composite increased. Cu/TiO2-CWSP composite showed the presence of very fine particles at the surface of composite in SEM micrograph having a zeta Potential value of −20.9 mV. In conclusion, this study presents an innovative approach for efficiently removing acid green dye from aqueous solutions through adsorption-photocatalysis synergy. The findings contribute to addressing the critical issue of water pollution, especially in the textile industry, offering a sustainable path towards cleaner water resources.

A novel Zr-MOF and its In2S3/Zr-MOF heterojunction materials for decontamination of Cr(vi) and reactive blue 13 via fluorescence sensing detection and photochemical redox

A novel Zr-MOF and its heterojunction materials were designed, which perform highly efficient fluorescence quenching sensing of Cr(vi) ions, and photocatalytic decontamination towards Cr(vi) and reactive dyes under xenon lamp.

Boron-doped biochar-nano loaded zero-valent iron to activate persulfate for the degradation of oxytetracycline

Oxytetracycline has posed a serious environmental nuisance, and seeking environmental decontamination materials is the priority task to deal with antibiotic water contamination. Herein, boron-doped biochar loaded nano zero-valent iron composites (nZVI/BBC) were fabricated as activators of PDS for oxidative degradation of oxytetracycline hydrochloride (OTC), and the main removal mechanism was explored in detail. The results showed that Boron-doped biochar with borate ester structure (BC2O) and degree of defects are the main active sites for improving PDS activation properties. BBC could effectively prevent nZVI agglomeration and reduce nZVI passivation. The effects of calcination temperature of BBC, loading ratio and dosage of nZVI/BBC, PDS concentration, initial solution pH, pollutant concentration, and interfering ions on OTC removal by nZVI/BBC were also systematically investigated, and the optimal reaction conditions were screened: 10 wt% loading of nZVI in the composite, 1 g/L dosage of nZVI/BBC, 1 mM dosage of PDS and solution pH= 5. The cycling test showed that the removal rate of OTC by nZVI/BBC decreased from 95.3% to 70.2% after five cycles, indicating that there is excellent stability of this material. Among them, the catalyst of 10%nZVI/BBC displayed the optimal PDS activation performance, owing to the synergistic adsorption-double oxidation system, BBC as well as nZVI. The free radical quenching experiment and free radical trapping experiment proved that the degradation of OTC mainly followed the free radical pathway and SO4•− and •OH were the primary active species in the catalytic system. This study provides a practical reference for the treatment of actual antibiotic wastewater.

Gamma irradiation-enhanced performance of waste LLDPE thermally transformed into advanced sponge-like material for oil decontamination

In this study, the development of advanced materials for the removal of oil–water pollution was explored, with a focus on environmental protection. The primary novelty of this research involved the conversion of waste Linear low-density polyethylene (LLDPE) into a sponge-like material denoted as sLLDPE. The process of converting involved thermal treatment in castor oil, resulting in the creation of a porous structure within the material. This sLLDPE material exhibited remarkable oil adsorbent properties and demonstrated enhanced performance in the removal of various organic contaminants from both aqueous and oil-based systems. Furthermore, gamma irradiation-induced crosslinking reactions were implemented within a dose range of 0 up to 90 kGy to further improve its oil removal capabilities. Comparing samples subjected to a radiation dose of 50 kGy with those receiving no irradiation (0 kGy), it was observed that the maximum adsorption capacities for various oils, including crude oil, gasoline oil, motor oil, pump oil, and waste oil, increased significantly. Specifically, the adsorption capacities increased by approximately 216.2%, 235.3%, 24.1%, 111.5%, and 18.6% for the respective oils. It rapidly separated oil–water mixtures with ~ 100% efficiency in a column system and maintained performance over 20 reuse cycles. The converted sLLDPE sponge exhibited excellent organics removal across solvents. The findings of this study not only shed light on the impact of irradiation on polymeric materials but also contribute to our understanding of their potential applications in environmental cleanup processes.

The Effect Decontamination of Sodium Hypochlorite 0.5% on shear strength buccal tube orthodontic

Background: The use of fixed orthodontics has a risk of increasing plaque retention, especially the gingival margin area. The decontamination material commonly used is sodium hypochlorite 0.5%, but this antibacterial agent requires further research on the shear strength of the buccal tube attachment. The purpose of this study was to determine the effect of 0.5% sodium hypochlorite on the shear strength of buccal tube attachment after decontamination 
 Method: The research design used was the post test only control group design. The total research sample amounted to 52 samples and was divided into 4 groups: group I Clorhexidine 2% for 1 minute, group II Clorhexidine 2% for 5 minutes, group III 0.5% NaOCl for 1 minute and group IV NaOCl 0, 5% for 5 minutes. Post Decontamination of Buccal Tube and bonding shear strength was carried out using Universal Testing Machine. The Kruskal Wallis test was carried out to see the differences in the four groups in the shear strength of attachment and the Mann Whitney test to find out the differences between groups. 
 Result: The shear strength of the attachment by decontamination using 2% chlorhexidine for 1 minute was higher than the other 3 groups, which was 25.3 J/mm2, the lowest shear strength was for the 0.5% sodium hypochlorite group for 5 minutes, which was 16.5 J/mm2. Kruskal Wallis test results p value 0.000 (p

Synthesis and characterization of TiO2-carbon filter materials for water decontamination by adsorption-degradation processes

Wastewater treatment is becoming ever more challenging due to the increasing levels of molecular pollutants that are challenging for existing approaches. Innovative materials are required to help produce potable water from heavily contaminated water sources. One such material is titanium dioxide-activated carbon (TiO2/AC) heterostructures, which combine the photocatalytic properties of TiO2 with the adsorption properties of the ACs. To date, studies on TiO2/AC heterostructures for real-world water purification have yet to be performed. This study aimed to address this gap by comparing the effectiveness of titanium isopropoxide (Ti(OiPr)4) and titanium butoxide (Ti(OBu)4) for synthesizing TiO2/AC heterostructures using four different methods (sol-gel, solvothermal, and microwave-assisted hydrothermal methods [x2]). The elaborated heterostructures were compared with commercial TiO2 materials for their ability to degrade five emerging contaminants (caffeine, hydrochlorothiazide, saccharin, sulfamethoxazole, and sucralose). Hydrochlorothiazide and sulfamethoxazole were demonstrated to be rapidly degraded by UV-C irradiation within 15 min. Caffeine, saccharin, and sucralose were less susceptible to UV degradation. All the elaborated TiO2/AC heterostructures consisted of pure anatase phase, with Ti(OBu)4 syntheses generating larger average crystal sizes and lower surface areas. Sol-gel preparations produced the most effective TiO2/AC heterostructures due to their high surface area. Compared with the commercial TiO2, the heterostructures enhanced the photocatalytic activity of TiO2 by up to 10.0 times. Also, the heterostructures remained effective at environmentally relevant conditions (i.e., concentration of the contaminant and water matrices). The reuse of the materials was tested and showed no reduction in efficiency after four removal/regeneration cycles. Overall, this study presents novel TiO2/AC heterostructures with increased photocatalytic efficiency that can serve as an efficient material for removing contaminants at large scales (e.g., water treatment plants).

Management of decontamination in chemical accidents: a laboratory model

Rapid and efficient decontamination of the skin is a major task for emergency rescue services in the event of a chemical accident involving humans. While rinsing the skin with water (and soap) has been the standard procedure, some skepticism has developed in recent years regarding the situational suitability of this method. The efficacy of three different decontamination materials/techniques (Easyderm® cleaning cloth, water-soaked all-purpose sponge, rinsing with water) in removing Capsaicin, Bromadiolone, Paraquat and 2,2′-dichlorodiethylether (DCEE) from porcine skin was compared. Different cleaning motions (wiping, twisting, pressing) with the Easyderm® were evaluated for their effectiveness in removing Capsaicin from porcine skin. Finally, the impact of different exposure times of the skin to Capsaicin on the decontamination process were investigated. Contaminant recovery rates (CRRs) were analysed in the skin and in each decontamination material using high-performance-liquid-chromatography (HPLC; used for Capsaicin, Bromadiolone, Paraquat) or gas chromatography (GC; used for DCEE). Wiping the skin with the amphiphilic Easyderm® was most effective for decontamination of Capsaicin and DCEE, while the water rinsing method gave the best results for removing Paraquat and Bromadiolone. Both wiping with the Easyderm® and rotating the Easyderm® were significantly more effective in cleaning Capsaicin-contaminated skin than pressing the Easyderm® on the contamination area alone. Prolonged exposure times of the porcine skin to Capsaicin were associated with a decrease in efficacy of the following decontamination. Emergency rescue services should have materials available that can remove both hydrophilic and hydrophobic substances from skin. Since not all of our results for comparing different decontamination materials were as distinct as we expected, there are likely several other factors determining the efficacy of skin decontamination in some cases. Time is key; therefore, first responders should try to begin the decontamination process as soon as possible after arriving at the scene.

РЕЗУЛЬТАТЫ ИСПЫТАНИЙ СОРБЦИОННЫХ МАТЕРИАЛОВ ДЛЯ ИЗВЛЕЧЕНИЯ РАДИОНУКЛИДОВ ЦЕЗИЯ ИЗ ЩЕЛОЧНЫХ ВЫСОКОАКТИВНЫХ ОТХОДОВ ФЕДЕРАЛЬНОГО ГОСУДАРСТВЕННОГО УНИТАРНОГО ПРЕДПРИЯТИЯ «ПО “МАЯК”»

The research results are presented of sorption extraction of cesium from alkaline high-level waste solutions stored in Mayak tanks using the resorcinol-formaldehyde resin RFS-i and modified nickel ferrocyanide-based inorganic sorbent Fersal. It is shown that the overall sorption performance of the Fersal exceeds that of the RFS-i. However, unlike the Fersal, the RFS-i remains stable during repeated cycles. A preliminary conclusion has been drawn on the prospects of use of both sorption materials for decontamination of Mayak real alkaline HLW.

Sustainable green conversion of coal gangue waste into cost-effective porous multimetallic silicate adsorbent enables superefficient removal of Cd(II) and dye

Converting solid wastes into new materials for wastewater decontamination is a feasible “one stone, three birds” strategy to achieve sustainable value-added utilization of resources and minimize waste emissions, but significant challenges remain. In response to this, we proposed an efficient “mineral gene reconstruction” method to synchronously transform coal gangue (CG) into a green porous silicate adsorbent without using any harmful chemicals (i.e., surfactants, organic solvents). The one of the synthesized adsorbents with a high specific surface area (582.28 m2/g) and multimetallic active centres shows outstanding adsorption performance (adsorption capacities: 168.92 mg/g for Cd(II), 234.19 mg/g for methylene blue (MB); removal rate: 99.04% for Cd(II) and 99.9% for MB). The adsorbent can also reach a high removal rate of 99.05%∼99.46% and 89.23%∼99.32% for MB and Cd(II) in real water samples (i.e., Yangtze River, Yellow River, seawater and tap water), respectively. After 5 adsorption-desorption cycles, the adsorption efficiency remained above 90%. The adsorbents mainly adsorbed Cd(II) by electrostatic attraction, surface complexation and partial ion exchange and MB by electrostatic and hydrogen bonding interactions. This study provides a sustainable and promising platform for developing a new-generation cost-efficient adsorbent from waste for clean water production.

Magnetic MOF composite material for decontamination of direct red 81 from polluted water

Herewith, magnetic Zn MOF composite material was utilized as an efficient adsorbent for direct red 81 “DR81” dye from wastewater. The synthesized magnetic MOF was characterized using X-ray diffraction (XRD), field emission transmission electron microscopy (FETEM), Fourier-transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), thermal gravimetrical analysis (TGA), and Brunauer-Emmett-Teller (BET) surface area analysis. The adsorption profile of DR81 anionic dye onto the prepared magnetic MOF was investigated with various processing parameters such as contact time, dosage, and initial dye concentrations. The optimum dosage from the fabricated magnetic Zn MOF for decontamination of DR81 was 1.0 g l−1 at pH = 7 after 30 min. The maximum Langmuir monolayer adsorption capacity of the DR81 decontamination via the synthesized magnetic MOF was recorded 67.35 mg g−1. These promising data confirmed the availability of the synthesized magnetic MOF composite as an excellent adsorbent material for the adsorption of DR81 from aqueous media.

Uklanjanje metomila iz vodenih rastvora korišćenjem mikrosfera reaktiviranog aktivnog uglja

The removal of methomyl, one of the most frequent pesticides, from aqueous solutions has been studied by adsorption using the reactivated carbon microspheres separated from worn filtering protective suits. This study is significant in two aspects - the first is the in-situ adsorption of pesticides from aqueous solutions, and the second is recycling protective equipment as an effective material for water decontamination. Carbamate pesticide, methomyl is aimed to control foliage and soil-borne insect pests on various agricultural product. Also, due its toxicity, it has a great potential for usage in terroristic acts and tactical purposes during military operations. The reactivated carbon (RAC) microspheres were characterized by Scanning Electron Microscopes (SEM). The changes in relative concentration of methomyl during the adsorption onto the surface of the RAC microspheres was determinated using the UV-Visible spectrophotometer. The adsorption process is described by Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich adsorption isotherm models. The adsorption kinetics follows the second-order kinetics model, and the thermodynamics study confirms that the adsorption is exothermic and spontaneous. At optimal conditions, the adsorption capacity was qe = 8.631 mol g-1 × 10-8 and the adsorption rate was k = 0.749 g mmol-1 min-1. The Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich adsorption isotherm models were used to describe the adsorption process. The thermodynamic study of adsorption proves the process is spontaneous with exothermic nature.

Magnetic Biochar by One-Step Impregnation Pyrolysis of Peganum harmala L. for Removal of Rhodamine B

A new magnetic P. harmala biochar/Mn-ZnFe2O4 material was prepared by the one-step pyrolysis approach and characterized by FT-IR, SEM, XRD, and BET techniques. The efficacy of removing rhodamine B (RhB) via adsorption and catalytic degradation was examined. Adsorption removal attained 82% of 10 mg·L-1 RhB at pH 4.0, 90 min of agitation, and 3.2 g·L-1 of adsorbent. The adsorption kinetics indicated a diffusion-limited mechanism and matched the second-order model. The equilibrium data are better suited by the Langmuir isotherm, and the maximum monolayer adsorption capacity ([Formula: see text]) was 34.5 mg·g-1. The D-R and Tempkin isotherms both showed an endothermic chemical adsorption process and negligible lateral repulsive forces, respectively. The catalytic removal by Fenton-like degradation was 40 and 99%, respectively, for the biochar/H2O2 and biochar/Mn-ZnFe2O4/H2O2. The prospective use of P. harmala biochar/Mn-ZnFe2O4 as an alternative material for RhB decontamination of water was validated by the successful removal of RhB from industrial wastewater of greater than 77% by adsorption and of 95% by the catalytic degradation.