Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Kaixuan Feng,Ruixiang Lin,Tingyu Chen,Yuyan Hu,Yuheng Feng,Dezhen Chen,Mudassir Hussain Tahir,Tongcheng Cao
In this study, a catalytic system for N 2 O reduction by H 2 onto char decorated with transition metals is proposed, which have excellent reduction efficiency at low temperatures below 200 °C and efficiently utilizes pyrolysis char and hydrogen. Density functional theory (DFT) is used to reveal the reaction mechanism and found that transition metal decoration can significantly promote reaction rate and decrease the activation energy required for N 2 O reduction by H 2 on char, from 383.7 kJ/mol to 50–160 kJ/mol. Furthermore, transition states in the process of reducing N 2 O by H 2 over metal-char were observed, including reduction of N 2 O and the removal of the surface oxygen complex. Through kinetic analysis , the activation energy and reaction rate order was found as Ni-char (50.0 kJ/mol)>Co-char (95.1 kJ/mol)>Fe-char (151.0 kJ/mol)>Cu-char (158.8 kJ/mol). According to experiments phenomenon, the sequence of reduction efficiency over different metal-char was consistent with the simulation results and it was even possible to convert N 2 O to N 2 below 200 ℃. This research contributes to a more mechanistic understanding of the N 2 O-H 2 reaction over char and provides new insights for improving the design of catalysts for N 2 O abatement at low temperatures.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2022
·Vol. 23
·期 17
·10094
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IF 6.208
Xiaoxin Chen,Gengxin Yu,Yuanhui Chen,Shanshan Tang,Yingjie Su
Cow dung (CD) is a waste product of livestock production. Improper disposal of a large amount of CD will cause environmental pollution. In this work, three biochar materials based on CD (BMCD) were prepared by using three types of base, including KOH, NaOH, and mixed base (MB, a mixture of equal mass NaOH and KOH) as activators to investigate the different physicochemical properties of BMCDs (BMCD-K, BMCD-Na, and BMCD-MB). The objective was to verify the effectiveness of MB activation in the preparation of biochar materials. The results show that MB has an effect on the structural characteristics of BMCDs. In particular, the surface area and total pore volume, the specific surface area, and the total pore volume of BMCD-MB (4081.1 m2g−1and 3.0118 cm3g−1) are significantly larger than those of BMCD-K (1784.6 m2g−1and 1.1142 cm3g−1) and BMCD-Na (1446.1 m2g−1and 1.0788 cm3g−1). While synthetic dye rhodamine B (RhB) and antibiotic tetracycline hydrochloride (TH) were selected as organic pollutant models to explore the adsorption performances, the maximum adsorption capacities of BMCD-K, BMCD-NA and BMCD-MB were 951, 770, and 1241 mg g−1for RhB, 975, 1051, and 1105 mg g−1for TH, respectively, which were higher than those of most adsorbents. This study demonstrated that MB can be used as an effective activator for the preparation of biochar materials with enhanced performance.Keywords:industrial wastewater;organic pollutants;cow dung;biochar materials;adsorption
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
MATERIALS LETTERS
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2015
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IF 2.489
Cungui Zhong,Shilei Gong,Li’e Jin,Ping Li,Qing Cao
Coal tar pitches (CTP) are used as precursor of electrode material because of their low cost and high carbon yield. In this study, CTP-based activated carbon materials (CACs) with high capacitance for supercapacitors were prepared by doping elemental N with co-carbonization of CTP and melamine. The electrochemical performance and textural characterization of CACs were investigated by constructing a single electrode capacitor in a 6 M KOH electrolyte, N 2 adsorption, scanning electron microscopy, and XPS. Results show that CACs with mass proportion of melamine and CTP being 1:5 possess a surface area of 2573 m 2 g −1 , with mesopore volume accounting for 56% of the total volume. After co-carbonization, N content on the surface of the CACs increased by 134% compared to that of undoped activated carbons. Their capacitance reached up to 228 F g −1 at a current density of 1 A g −1 . The high electrochemical performance of the CACs is attributed to its additional pseudo-capacitance and high surface area. The specific capacitance still possessed 94.2% retention after 1000 cycles, indicating good cycle stability.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Yuxin Qi,Ying Bi,Chao Kong,Changyin Zhu,Hu Cheng,Yinlong Zhang,Jiangang Han,Jianming Xue,Ziyan Li,Yang Song,Dongmei Zhou
Recycling difficult-to-degrade plastics, also known as “white pollution”, is currently being researched in the fields of materials and the environment, which is an extremely challenging topic. In this study, a pyrolysis-activation method combined with multiple activators was developed to prepare stable porous plastic chars (PPCs) from discarded plastic bottles for removing the typical antibiotic sulfamethoxazole (SMX). Micro/mesopores were formed in the PPCs, with the specific surface area reaching 961.20 m 2 /g. C, O, and N were the main elements in the PPCs, and their atomic ratios showed the hydrophobicity and aromaticity. Graphite-like structures and abundant surface functional groups were generated in the PPCs. Unlike conventional char materials, impurities, such as aluminum oxide, have high reflectivity, resulting in the appearance of many shining spots. PPCs display a high sorption capability for SMX, with the maximum sorption quantity determined reaching 487.52 mg/g. Multilayer sorption is dominated by physical processes, and pore filling, partitioning, hydrogen bonding, π-π stacking, and electrostatic interactions are the main sorption processes. Chemical-like sorption and mass transfer control the sorption rate. Furthermore, PPCs have stable performance and good recyclability and could be used for practical applications. This study provides a novel strategy and an example of the upcycling of discarded plastic as an excellent char material for environmental remediation.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Yang Hao,Hao Wang,Rui Han,Caixia Liu,Qingling Liu
Treating wastewater with elevated ammonia nitrogen levels in garbage treatment plants is a global concern, with blow-off recognized as an efficient process for nitrogen removal. However, this method generates low-concentration ammonia, presenting a challenge for adequate recovery. This study addresses this issue by impregnating metal halides onto K 2 CO 3 -activated biogas residue to create composite materials tailored for adsorbing low-concentration ammonia. We systematically investigated the impact of activation parameters, metal halide type, loading capacity, and environmental conditions on the adsorption properties of the materials. Notably, at an activation temperature of 700 °C, utilizing copper chloride with a loading capacity of 30 %, the material exhibited a saturation adsorption capacity of 29.32 mg/g for 200 ppm NH 3 , with a breakthrough time of 45.6 min, significantly surpassing the untreated sample and demonstrated excellent regeneration performance. SEM, BET, and FTIR analyses revealed that the material provided dispersion sites for metal halides, promoted the complexation of metal halides and ammonia and retained pores for ammonia diffusion, thereby enhancing adsorption efficiency. This innovative approach contributes to waste utilization and ensures efficient ammonia recovery through metal halide-ammonia complexation.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CARBON
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2022
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IF 11.307
Yi Sun,Yudan Yuan,Xianwei Geng,Chi Han,Shenkai Lu,Ivona Mitrovic,Li Yang,Pengfei Song,Cezhou Zhao
A simple hydrothermal reaction of Ti 3 C 2 T x and reduced graphene oxide (rGO) nanosheets to adjust the pore size of activated biomass materials (pleurotus eryngii) is presented. The unique structure produced is favourable for the ion transmission and reducing the restacking of Ti 3 C 2 T x and rGO nanosheets. The effect of the addition quantities of Ti 3 C 2 T x /rGO hydrogel on the specific capacitance is investigated. Under the optimal condition, the best specific capacitance of 403 F g −1 is observed at 2 mV s −1 , which is approximately 1.5 times higher than that of the pure activated pleurotus eryngii. Our work possesses a technological strategy to reuse the commercial activated biochar as it can lead to broad industrial applications.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Green Chemical Engineering
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2024
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IF 9.1
Zhihong Ma,Weizhong Zheng,Kexin Yan,Qiaoling Zhang,Weizhen Sun,Ling Zhao
Waste H 2 SO 4 from industrial isobutane alkylation, a hazardous thick liquid with a high concentration of acid soluble oil (ASO) impurities, poses challenges in the regeneration process. Herein, an innovative low-temperature carbonization process was proposed to convert waste H 2 SO 4 into the regenerated concentrated H 2 SO 4 and sulfonated activated carbon materials (SACMs) under mild reaction conditions. The optimal reaction temperature is identified at 423.15 K with the highest TOC removal of 90.57%. The high-purity regenerated H 2 SO 4 with a concentration of 95% as a catalyst for isobutane alkylation exhibits excellent catalytic performance with 94.54 research octane number (RON) of the alkylate. SACMs, characterized as a novel porous carbon material with plentiful hydroxyl, carboxylic acid, and sulfonic acid functional groups, demonstrate an efficient catalytic activity in the dimerization of lactic acid to produce lactide with a yield of 46.95%. Hopefully, the novel recovery process provides a promising application to optimize the regeneration process of waste H 2 SO 4 from industrial isobutane alkylation.
研究领域:
化学工程
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环境科学
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催化材料
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DOI
高影响因子
Processes
·
2023
·Vol. 11
·期 9
·2577
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IF 3.5
Cancan Xu,Rui Liu,Lvjun Chen
In order to promote the improvement of rural living environments, the treatment of rural domestic sewage has attracted much attention in China. Meanwhile, the rural regions’ sewage discharge standards are becoming increasingly stringent. However, the standard compliance rate of the total phosphorus (TP) is very low, and the TP has become the main limiting pollutant for the water pollutant discharge standards of rural domestic sewage treatment facilities. In this study, oyster shell waste was employed as a calcium source, and agricultural waste–rice husk was used as a carbon source to synthesize calcium-modified biochar adsorbent materials (Ca-BC) by a simple one-step pyrolysis method. The resultant Ca-BC adsorbent materials demonstrated efficient phosphate (P) adsorption from aqueous solutions over a wide pH range (3–11) and adsorption selectivity. Ca-BC’s adsorption capacity for P increased with the pyrolysis temperature, increasing from 700 °C to 900 °C, which was attributed to the higher specific surface area and calcium oxide content at higher pyrolysis temperatures. The Ca-BC sample, which was made from oyster shells and rice husks with a mass ratio of 2:1 and a pyrolysis temperature of 900 °C, had a maximum adsorption capacity of 196.2 mg/g. The Langmuir model and pseudo-second-order model were the best at describing the adsorption process, and the predominant sorption mechanism for P is the precipitation of calcium oxide or calcium hydroxide with phosphate to create hydroxyapatite. Ca-BC can effectively remove P from rural domestic sewage. The removal rate of the total phosphorus (TP) in rural domestic sewage is 93.9–99.4%. After the adsorption treatment, the discharge of the TP in the rural sewage met the second-grade (TP < 3 mg/L) or even the first-grade (TP < 2 mg/L) Discharge Standard of Water Pollutants for Centralized Rural Sewage Treatment Facilities (DB33/973-2021). This study provides an experimental basis for efficient P removal by Ca-BC adsorbent materials and suggests possible applications in rural domestic sewage.Keywords:agricultural waste utilization;modified biochar material;phosphate adsorption;rural domestic sewage;discharge standard
研究领域:
环境科学
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水处理技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）