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In this article, buckthorn twigs were used to prepare activated carbon preparation by chemical activation with a microwave technique for removing diesel oil from water. buckthorn twigs and activated carbon were characterized by FESEM, EDX, and FTIR analysis techniques. Design-Expert (13 Stat-Ease) with Response Surface Methodology (RSM) was selected to identify and analyze the effects of activated carbon preparation factors. These factors include impregnation ratio, impregnation time, and microwave power with exposure time on the adsorption of methylene blue dye (MBN). Likewise, the effects of adsorption factors including; diesel oil concentration, pH, adsorption time, and adsorbent dosage on the removal efficiency were studied. The results showed that the maximum removal efficiency was 96.0823% with the significance of all adsorption factors. The adsorption data were fitted with the adsorption isotherm and kinetics models. The results showed that Freundlich and second-order kinetic models well described diesel oil adsorption, thus elucidating the applicability of multilayer and chemosorption processes. In addition, the thermodynamics parameters of diesel oil adsorption were determined, and the results demonstrated a spontaneous and endothermic adsorption process.

Medical wastewater is a significant contributor to environmental pollution, posing severe risks to both human health and the environment. To resolve this challenge, the removal of anti-cancer drugs from medical wastewater has been considered. This study investigated the removal of doxorubicin, an effective anti-cancer drug, from an aqueous solution using three types of adsorbents: activated carbon, multi-walled carbon nanotube, and montmorillonite. Our findings revealed that carbon nanotubes exhibited superior performance in doxorubicin removal from water compared to the other two adsorbents. Specifically, the maximum adsorption capacity of doxorubicin with an initial concentration of 50 mg L–1 on the carbon nanotube reached 500 mg g–1. In addition, surface modification of the adsorbents with acid resulted in a 15 % and 41 % increase in adsorption capacity, and an 85 % and 67 % reduction in equilibrium time for carbon nanotube and montmorillonite, respectively. The increasing pH proved to enhance the adsorption efficiency of carbon nanotubes and activated carbon, with the best performance achieved at solution pH of 10 and 8 for MWCNTs and AC, respectively.

Abstract A static batch arrangement composed of anti-leak vials coupled to gas chromatography is proposed as a complementary system for performance assessment of biogas desulfurization by adsorption. For testing, a modified commercial activated carbon produced by controlled thermal treatment in the presence of iron(III) species improved biogas desulfurization. The adsorbents showed a superior hydrogen sulfide removal compared to ordinary one. Pseudo-first-order, pseudo-second-order, and Bangham’s kinetic models were used to fit experimental data. All studied samples followed pseudo-first-order model, indicating the predominance of physisorption, and Bangham’s model, confirming that the micropores structure played an important role for gases diffusion and adsorbent capacity. Additionally, the materials were characterized by N2 adsorption–desorption, X-ray diffraction, infrared spectroscopy, scanning electron microscopy and energy-dispersive spectroscopy. The thermal treatment associated with iron impregnation caused significant modifications in the surface of the materials, and the iron species showed two main benefits: an expressive increase in the specific area and the formation of specific adsorption sites for hydrogen sulfide removal. The results reinforce the advantages of iron-modified adsorbents in relation to their non-modified counterparts. The analytical methodology based on the confinement of multiple gases contributes to improving the understanding of the hydrogen sulfide adsorption process using pressure swing adsorption technology. Graphical Abstract

Abstract Supercapacitors have emerged as highly efficient energy storage devices, relying on electrochemical processes. The performance of these devices can be influenced by several factors, with key considerations including the selection of electrode materials and the type of electrolyte utilized. Transition metal oxide electrodes are commonly used in supercapacitors, as they greatly influence the electrochemical performance of these devices. Nonetheless, ferrites' low energy density poses a limitation. Hence, it is crucial to create electrode materials featuring unique and distinct structures, while also exploring the ideal electrolyte types, to enhance the electrochemical performance of supercapacitors incorporating magnesium ferrites (MF). In this study, we effectively prepared magnesium ferrites (MgFe2O4) supported on activated carbon (AC) derived from orange peels (OP) using a simple hydrothermal method. The resulting blends underwent comprehensive characterization employing various methods, including FTIR, XRD, TEM, SEM, EDX, and mapping analysis. Moreover, the electrochemical performance of MgFe2O4@AC composites was evaluated using GCD and CV techniques. Remarkably, the MF45-AC electrode material showed exceptional electrochemical behavior, demonstrating a specific capacitance of 870 F·g−1 within current density of 1.0 A g−1 and potential windows spanning from 0 to 0.5 V. Additionally, the prepared electrodes displayed exceptional cycling stability, with AC, MF, and MF45-AC retaining 89.6%, 94.2%, and 95.1% of their initial specific capacitance, respectively, even after 5000 cycles. These findings underscore the potential of MF-AC composites as superior electrode materials for supercapacitors. The development of such composites, combined with tailored electrolyte concentrations, holds significant promise for advancing the electrochemical performance and energy density of supercapacitor devices.

Acid Mine Drainage (AMD) contains Fe(II) and Mn(II) metals, which can cause environmental pollution. This research aimed to investigate the potency of activated carbon made from coal as an adsorbent in AMD treatment. The carbon was made of coal and activated with H3PO4 in a weight ratio of 40%, 800 °C for 120 minutes while supplying 1.5 L/min of nitrogen during the carbonization process. The result shows that BET surface area, total pore volume, and iodine number were 296.4 m2/g, 0.156 cc/g, and 1205 mg/g, respectively. The surface contained many fractures, channels, and big holes, as evidenced by the FT-IR and SEM investigations, and it also had acidic surface functional groups. The optimum contact time adsorption for AMD treatment was 30 minutes, and the first concentration of Fe(II) and Mn(II) metals affected the adsorption. The optimum removal of Fe(II) in AMD treatment was 95.27% at an initial concentration of 3.51 ppm, while the optimum removal of Mn(II) was 99.82% at an initial concentration of 5.71 ppm. This activated carbon has a considerable potency to be used as the adsorbent in AMD treatment to reduce Fe(II) and Mn(II) levels.

To reduce the hazards brought by water hyacinth, many applications of water hyacinth have been studied and continuously expanded. The large biomass of water hyacinth is applied in many fields such as for wastewater treatment, wastewater purification, biological raw material sources, animal feed production, medicine, antioxidants, agriculture, and household appliances. This research investigates the desalination capacity of freshwater hyacinths, raw materials from water hyacinths, biochar, and activated carbon materials from water hyacinth stems. Results have shown that the suitable temperature for charring fresh water hyacinth is 420 °C. The activated carbon from the water hyacinth stems with a BET surface area of 200.4 ± 1.9 m²/g can be desalinated under the conditions of 0.4 g of activated carbon mass, 15 min of reaction time, 2.0 ppt of salt concentration, and at neutral pH. In contrast, raw materials from water hyacinths and biochar were unable to desalinate. This study evaluates the desalination ability of the activated carbon material of water hyacinth.

In the previous years, activated carbons (ACs) derived from agro-waste have demonstrated excellent adsorption capability. Production of ACs using easy available and low cost agro-waste marks them as unique materials for several environmental applications including but not limited to CO2 capture, dyes and heavy metal ion removal by adsorption etc. This review highlights the present scenario of available agricultural land, global agricultural production and generation of enormous agro-waste worldwide with their alternative management by producing value-added and applicable ACs as an adsorbent for environmental remediation instead of burning. This review specifically aims to support researchers by providing an all-inclusive overview of different aspects of agro-waste management with a perspective in AC preparation, characterization and its environmental applications such as CO2 capture, dye and metal ion adsorption for enhancing the pathways to clean air and water.

Under the background of the “dual carbon goal” era, hydrogen production from methane decomposition is considered to be a promising high-purity hydrogen production technology due to no CO2 emissions. The research on carbon catalyst modification is a hot spot in related fields. To improve the stability of activated carbon (AC) catalysts, the new catalysts prepared by coconut shell activated carbon supported with carbon black (CB) ketjen black EC300J was proposed and prepared. And its characterization test analysis, catalytic methane cracking experiment and molecular simulation calculation were carried out. The results show that the catalyst prepared when the amount of dispersant was 1 g and the AC and CB mass ratio was 8∶2 had better catalytic performance, the initial activity at 1 000 ℃ was up to 85%, the deactivation was delayed for 15 min, and the methane conversion in the middle stage of the reaction was about 8% higher than that in AC. This is because that CB is loaded on the surface of AC and generates deposited carbon with defect sites through reaction. The results of molecular simulation calculations show that the main reason is that the existence of topological defects increases the nonlocality of its s and p orbitals, which improves the adsorption performance of methane and promotes the reaction. In addition, the micropores on the surface of AC and oxygen-containing functional groups such as carboxyl, carbonyl, and hydroxyl groups also have different degrees of promotion on the adsorption of methane molecules. The heat of adsorption is the greatest when the pore size is 0.8 nm, which means that the presence of micropores is conducive to methane adsorption on AC, especially small micropores. All three functional groups can promote the adsorption of methane on the surface of AC, among which the carboxyl group promotion effect is better, and the carbonyl and hydroxyl effects are not much different.

Introduction. Phenols are one of the main organic components present in the effluents of many industrial enterprises. However, the discharge of wastewater containing phenol is a priority due to its high toxicity to humans and animals, even at low concentrations. Activated carbon (AC) adsorption, which is one of the advanced purification processes, is widely used to purify water pollutants and the production of activated carbon from several carbon by-products of agriculture was also reported. In this regard, the purpose of this research was to study the adsorption of phenol on activated carbon based on date palm branches (DPB-AC) as a low-cost adsorbent.Materials and methods. DPB was used as a raw material for the production of AC by chemical activation of H3PO4. Adsorption experiments were carried out in batches. The kinetics and isotherms of adsorption were also investigated.Results. DPB-AC was obtained by chemical activation of date palm branches using H3PO4 (600 ℃, 60 min), and the specimen was designated as (DPB-AC-H3PO4). The results showed an AC yield of 52.7 %. The maximum efficiency of phenol adsorption was achieved at pH 7. In addition, phenol adsorption was well described by the kinetics of the pseudo second order with K2 = 0.0503 g/(mg·min). The phenol adsorption isotherm model followed the Langmuir model, where R2 was 0.9215 and KL = 0.0161 l/mg at 180-equilibrium time. The maximum adsorption capacity of phenol was 77.52 mg/g (mg of phenol absorbed/g of DPB-AC-H3PO4), which is a high value compared to many other results presented in the literature.Conclusions. In general, the results indicate that AC obtained from date palm branches can be a promising material for wastewater treatment, as well as an effective means to solve environmental pollution problems.

Groundwater is very important part of life and source of survival on earth; and the clean water is one of the most important issues of the developed or developing world. In addition to other secondary problems such as solid waste and resource waste management, wastewater management is a major environmental obstacle to the development of the textile industry. Textile industry is the largest industrial sector of the world and hold very important part for the development of economy in all countries. Although the industry generates a lot of chemicals, including dyes in the form of wastewater. The textile industry is most fresh water consuming industry; simultaneously it discharges the huge load of contamination in our environment. The textile industry is the largest producer of wastewater during its different production processes. The wastewater creates several problems such as health problems, aquatic life including water pollution. The textile industry wastewater is treated by different methods such as coagulation, adsorption, membrane, and biological treatment. This paper reviews the different treatment technologies for textile wastewater along with its advantages and disadvantages. The objective of this study is to contribute a summary on the best and latest treatment techniques for textile industry effluent.

In this study, Titanium dioxide Nanoparticles (TiO2 NPs) were biosynthesized using the extract of Cola nitida (Kola nut) pod as a reducing agent. The synthesized TiO2 NPs were impregnated on the surface of Groundnut Shell Activated Carbon (GNSAC) to produce TiO2-NPs-GNSAC, and its performance on the removal of ibuprofen from pharmaceutical wastewater was investigated. The two adsorbents (GNSAC and TiO2-NPs-GNSAC) were characterized using proximate analysis, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Brunauer-Emmett-Teller (BET), and Energy Dispersive X-ray (EDX). Physical properties such as moisture content, ash content, and volatile matter content were also determined. The combined effects of three independent variables (temperature, time, and adsorbent dosage) were evaluated in a batch study designed through Box Behnken Design (BBD) of the Response Surface Methodology (RSM) for experimental design, analysis, and process optimization. Regeneration examinations were conducted for three cycles. The proximate analysis showed that GNSAC and TiO2-NPs-GNSAC have 63.21 and 71.11 % of carbon, respectively, which could be attributed to the high organic content in Groundnut Shell (GNS). BET analysis proved that the adsorbents (GNSAC and TiO2-NPs-GNSAC) were mesoporous with mean pore sizes of 6.046 and 5.353 nm, respectively. At optimum conditions of 0.62 g/L, 30 °C and 30 min for adsorbent dosage, temperature, and time, respectively, 68.53 % of ibuprofen was removed using GNSAC, while 81.78 % of ibuprofen was removed at optimum adsorbent dosage, temperature, and time of 0.5 g/L, 30 °C, and 50 min, respectively, using TiO2-NPs-GNSAC. Langmuir isotherm best described the equilibrium data using GNSAC and TiO2-NPs-GNSAC, with maximum monolayer adsorption capacities of 40.82 mg/g and 55.56 mg/g, respectively. Pseudo second-order kinetic model was more suitable to predict the experimental data. The mean free energy (E) values of 0.345 and 0.746 KJ/mol obtained for ibuprofen adsorption onto GNSAC and TiO2-NPs-GNSAC indicate that the mechanism of adsorption of ibuprofen follows the physisorption process. Based on the thermodynamic investigation of the current process, it can be concluded that the adsorption of ibuprofen by the prepared activated carbon (GNSAC and TiO2-NPs-GNSAC) was a spontaneous and endothermic process. Additionally, the adsorbent was successfully regenerated three times, and it was able to perform the adsorption and desorption processes well. Hence, the results of this work suggest that the activated carbon prepared from groundnut shell is a suitable adsorbent for the adsorption of ibuprofen from pharmaceutical wastewater.

Caused by pathogenic microorganisms, infectious diseases are known to cause high mortality rates, severe burdens of disability, and serious worldwide aftermaths. Drug-resistant pathogens have reduced the efficacy of available therapies against these diseases, thus accentuating the need to search for effective antimicrobials. Medicinal plants have served as starting material for the preparation of a number of antimicrobial agents. To this end, the present study highlights the green synthesis of Cocos nucifera-based nanomaterials and evaluation of the mechanistic basis of their antimicrobial action. Accordingly, Cocos nucifera extract was used for the reduction of silver nitrate solution to afford silver nanoparticles. These entities were further incorporated onto sulfuric-acid-based activated carbons to generate the nanocomposites. The antimicrobial activity of the as-prepared nanomaterials was evaluated using the broth microdilution method, while the antioxidant activity was assessed through standard methods. The cytotoxicity of potent nanomaterials was assessed on Vero cells by the spectrophotometric method. As a result, nanoparticles were successfully synthesized, as evidenced by the ultraviolet–visible spectroscopy analysis that revealed an intense absorption spectrum at 433 nm. Fourier Transform Infrared Spectroscopy presented the functional group moieties involved as a capping and reducing agent in the synthesis of the nanomaterials. The incubation of nanomaterials with selected bacterial and fungal strains has led to significant inhibitory effects of these pathogens with minimum inhibitory concentrations ranging from 7.813 to 250 μg/mL. In antioxidant assays, the nanocomposites presented scavenging activities comparable to those of ascorbic acid. Cytotoxicity experiment revealed no toxic effects on Vero cells (range of selectivity indices: from >4 to >128). These results provide evidence of the implication of Cocos nucifera-based nanomaterials in targeting bacterial or fungal systems that mediate free-radical damage or by inhibiting the oxidative damage caused by selected bacteria and fungi, the most susceptible being Escherichia coli and Candida albicans, respectively.

This study focuses on the synthesis of activated carbon (AC) using a mix of polyethylene terephthalate, (PET) and date seeds (DS) by the optimized ZnCl2-activation method for the first time. At 600 °C for 1h utilizing an impregnation ratio of 2:1 ZnCl2: mix, the ideal AC was synthesized. The latter was submitted to identification by N2 adsorption-desorption isotherms and pore volume, XRD, FESEM, EDX, total basic and acid groups, FTIR, and pHPZC, and the outcome suggested its mesoporous structure with an average pore size of 3.16 nm and a BET surface area of 672.22 m2/g. This AC was tried in the dispose of dibenzothiophene (DBT) from model oil (DBT/n-hexane), and the findings showed that the superlative elimination of DBT (95.07%) was accomplished at 35 °C for 80 min using 0.30 g of the AC. Eliminating DBT by the AC derived from the said mix was best represented by the Langmuir adsorption isotherm and pseudo-2nd-order kinetics model. An adsorptive capacity of 23.80 mg/g was obtained as per the Langmuir adsorption isotherm .The regenerated AC demonstrated an outstanding adsorptive performance for DBT up to 4 cycles of reuse, signifying its high adsorption performance.

Oil-palm shell wastes were successfully converted into useful activated carbons in a systematic and novel approach by optimizing the pyrolysis conditions and subsequent steam activation conditions to maximize the BET surface area. The optimal activation conditions were a steam flow rate of 1.13 kg/h, hold time of 1.5 h and temperature of 950 °C, yielding BET areas of 1432.94 and 1382.95 m2/g for nitrogen-pyrolyzed and vacuum-pyrolyzed chars, respectively. In steam-chemical activation, one-step activation of oil-palm shell in steam with potassium carbonate (K2CO3), sodium carbonate (Na2CO3) or potassium chloride (KCl) was conducted, resulting in BET area output order of shell/K2CO3 (710.56 m2/g) > shell/KCl (498.55 m2/g) > shell (366.7 m2/g) > shell/Na2CO3 (326.62 m2/g). This study reported the first use of KCl and Na2CO3 as chemical reagents in one-step steam-chemical activation of biomass. KCl-activated carbon exhibited retardation of tar formation property, resulting in better pore development than pure steam activated carbon.Phenol adsorption of activated carbon is not only a function of the BET surface area but also the type of pyrolysis used prior to physical activation. Activated carbon (BET area of 1192.29 m2/g) pyrolyzed under vacuum could adsorb 87% more phenol than that pyrolyzed in nitrogen flow which had a higher BET area of 1432.94 m2/g. Phenol adsorption capacities of activated carbons are: shell pyrolyzed under vacuum (275.5 mg/g) > shell pyrolyzed in N2 flow (147.1 mg/g) > shell/K2CO3 (145.7 mg/g) > shell without pyrolysis (12.1 mg/g). These activated carbons would be highly suitable in industry processes to remove phenolic contaminants.

Layered double hydroxides (LDH) can be transformed from alkaline supercapacitor material into metal-cation storage cathode working in neutral electrolytes through electrochemical activation. However, the rate performance for storing large cations is restricted by the small interlayer distance of LDH. Herein, the interlayer distance of NiCo-LDH is expanded by replacing the interlayer nitrate ions with 1,4-benzenedicarboxylic anions (BDC), leading to the enhanced rate performance for storing large cations (Na+, Mg2+, and Zn2+), whereas almost the unchanged one for storing small-radius Li+ ions. The improved rate performance of the BDC-pillared LDH (LDH-BDC) stems from the reduced charge-transfer and Warburg resistances during charge/discharge due to the increased interlayer distance, as revealed by in situ electrochemical impedance spectra. The asymmetric zinc-ion supercapacitor assembled with LDH-BDC and activated carbon presents high energy density and cycling stability. This study demonstrates an effective strategy to improve the large cation storage performance of LDH electrodes by increasing the interlayer distance. [ABSTRACT FROM AUTHOR]

A catalytic oxidation treatment to remove coloration and chemical oxygen demand (COD) in an effluent from a food industry was carried out using oxygen and ozone as oxidizing agents and activated carbon as a catalytic. Different experiments of oxidation were conducted using 25, 50 and 100 mL of activated carbon bed to treat 100 mL of sample and constant flow of oxygen 7.2 g/min and ozone 0.034 mg/min, maintaining initial pH of industrial effluent. Almost a complete coloration removal and COD reduction of the sample was achieved for catalytic processes; however, time of treatment and agent oxidant doses were different in each case. According to volume of activated carbon beds, ozone doses for discoloration and COD removal were 8.5, 2 and 1.7 mg/L, whereas the oxygen doses were 2860, 770 and 500 g/L, respectively. Consequently, to eliminate the color in the industrial effluent, the dose of oxygen was higher than that of ozone. In addition, the oxidation agents promoted the regeneration of activated carbon, showing that its activity is declined after 60 cycles of effluent treatment with ozone, whereas with oxygen treatment, the total depletion was observed in 18 cycles. In turn, single adsorption showed activated carbon depletion in 5 cycles of effluent treatment. [ABSTRACT FROM AUTHOR]

This study was planned to explore the AFM1‐reducing potential of various heat and acid‐killed lactic acid bacteria (LAB), activated carbon and bentonite (BENT) in milk contaminated with 0.5 μg/L AFM1 and their impact on milk composition. A negligible impact was observed on milk composition with AC while exhibiting a higher AFM1 removal (78.2%) than bentonite (35.8%). Their combination with LAB cells increased AFM1 decontamination for most of the treatments, with highest AFM1 removal (97.6%) exhibited by a treatment involving 0.1% AC and acid‐killed cells of L. cremoris. The results of this study indicate that LAB cells associated with the adsorbents tested are highly effective in reducing milk AFM1 content. [ABSTRACT FROM AUTHOR]

Summary: This research was designed to examine the effects of activated carbon dosage and pH on various attributes of corn protein hydrolysate, including decolourization efficiency, nitrogen component, amino acid (AA) composition, protein secondary structure, and antioxidant activity. Optimal pigment elimination of occurred within the pH range of 2.0–4.0, utilising the hydrolysate as the control. Remarkably, the removal of trichloroacetic acid (TCA) insoluble peptide was evident at pH 4.0. The decolourization process elicited considerable reduction of the aromatic AA, exhibiting pronounced decreases of acidic AA (Glu and Asp) within the pH range of 2.0–4.0, and basic AA (His, Lys, and Arg) within the range of 6.0–8.0. Meanwhile, infrared spectroscopy analyses indicated that a dosage of 0.5% activated carbon at pH 4.0, effectively preserved the secondary structure and ratios of the control, maintaining its antioxidant activity. These results provide insights into optimisation strategies for decolourization in the food industry. [ABSTRACT FROM AUTHOR]

The output power and combination property of microbial fuel cells (MFCs) are often limited by the sluggish kinetics of the cathodic oxygen reduction reaction (ORR). Therefore, seek noble metal-free materials with good ORR catalytic efficiency and durability is of great significance for practical MFC application. In this paper, ternary transition metal sulfide was successfully loaded on activated carbon by hydrothermal method. In the MnCo2S4@AC nanocomposite, the synergistic effect existing between MnCo2S4 and activated carbon (AC) gives the advantages of large specific surface area, special microstructure, fast electron transmission rate and good electro-catalytic activity of MnCo2S4 for ORR. The electrochemical tests showed that the ORR event of MnCo2S4@AC was the four-electron (4e−) pathway. Therefore, the highest output power density of MFC assembled with MnCo2S4@AC was 239.41 mW m−2, 3.59-fold stronger than AC (66.66 mW m−2). This method can provide the ideas for the synthesis of efficient ORR catalyst. [ABSTRACT FROM AUTHOR]

Concern over safe drinking water has increased. In this study, aluminum oxide was coated with carbon nanotubes by chemical vapor deposition using ethanol or methanol as precursors to remove N-nitrosamines, 2-methylisoborneol (MIB) and geosmin from water. Seven types of N-nitrosamines were investigated. The differences in the surface of the carbon nanotubes were attributed to the carbon precursors ethanol and methanol. Despite the high concentration of analytes, the adsorption capacity of both carbon nanotubes (CNTs) was around 19 mg/mg for MIB and geosmin. Against approximately 0.9 ng/mg for activated carbon. For N-nitrosamines, the adsorption capacity of CNTs reached 50 ng/mg for NDBA, N-nitrosamines with the highest molecular weight, while activated carbon had values below 6.0 ng/mg. The results showed π-π interactions play a dominant role in the adsorption of MIB and geosmin under the investigated conditions. On the other hand, for N-nitrosamines, both dipole-dipole and π-π interactions come into play, with the latter becoming more prominent as the molecular weight of N-nitrosamines increases. The removal efficiencies of CNT-coated aluminum oxide reached 84,0%. The analytes with longer carbon chains were removed more efficiently and CNT-coated aluminum oxide grown from ethanol or methanol had no statistical difference between the removal efficiencies of all evaluated analytes. [ABSTRACT FROM AUTHOR]

[Display omitted] Adsorbents with dual-component active phases have attracted much attention owing to their potential application in synergistic H 2 S removal. The influence of spatial arrangements of two components within a support matrix on their desulfurization performance was investigated through regulating the mutual arrangements of CuO and MgO on an activated carbon surface. Their spatial locations were found to remarkably affect interfacial interactions, local pH, the conductivity of adsorbents, and electronic structure of copper oxide. A close contact of CuO with the carbon surface led to strong interactions of both components, inhibiting the reduction of CuO and decreasing its reactivity with H 2 S. On the other hand, a proximity of MgO to the carbon surface increased local pH, promoting the oxidation of H 2 S into elemental S, instead of sulfates. Cu+ in the copper oxide phase increased the desulfurization performance due to its ability to activate oxygen and to accelerate a lattice diffusion. Enhanced surface conductivity due to the interfacial interactions improved the desulfurization efficiency and favored the formation of elemental S through promoting an electron transfer in redox reactions. [ABSTRACT FROM AUTHOR]

Overuse of antibiotics causes environmental pollution, and activated carbon adsorption is an effective way to remove antibiotics from polluted water. Herein, a cost-effective biomass carbon adsorbent for the adsorption of chloramphenicol (CHL) was prepared from pomelo peel using KHCO3 activator. The activated carbon boasted a significant specific surface area (SBET) of 1608 m2 g−1 with a maximum adsorption capacity (Qmax) for CHL reaching 549.5 mg g−1. The effect of adsorption behavior on adsorption capacity was studied. The adsorption process followed the pseudo-second-order kinetic and Langmuir models. From combined FT-IR and XPS data, the adsorption action included both physical adsorption and chemical adsorption. The rate-limiting step was diffusion through the boundary layer. The adsorption mechanism mainly included the processes of pore filling, functional group binding, and hydrogen bond and π–π interactions. Thermodynamic parameters demonstrated spontaneous and exothermic properties. This work demonstrated the rational application of waste biomass carbon for efficient adsorption of antibiotics to provide new help for antibiotic removal from polluted water. [ABSTRACT FROM AUTHOR]