ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 9
·8902-8913
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IF 2.914
Sun Chen,Chen Tong,Huang Qunxing,Wang Jun,Lu Shengyong,Yan Jianhua
Novel KMnO 4 -treated magnetic biochar (FMBC) was successfully synthesized by addition of Fe(NO 3 ) 3 during carbonization and KMnO 4 treatment following for Pb(II) and Cd(II) adsorption. SEM-EDS, XPS, and ICP-AES were used to evaluate the FMBC and magnetic biochar (FBC) on surface morphology, surface chemistry characteristics, surface functional groups, and Pb(II) and Cd(II) adsorption behavior. Results showed that the Langmuir maximum adsorption quantity of FMBC reached 148 mg/g for Pb(II) and 79 mg/g for Cd(II), nearly 7 times of that of FBC. The enhancement of FMBC for heavy metal adsorption was due to the successful load of manganese oxides and the increased oxygen functional groups consistent with XPS and FTIR results. The adsorption capacities of FMBC were maintained over 95% when the pH value was higher than 2.5 and 3.5 for Pb(II) and Cd(II), respectively. The adsorption performances of both heavy metals by FMBC were hardly influenced by ionic strength and humid acid. The adsorption capacities of FMBC could maintain over 50% and 87% after four cycles for Pb(II) and Cd(II), respectively. The saturation magnetization of FMBC was about 11.5 emu/g, which did not change after adsorption. This work proposed a new method to fabricate a magnetic biochar with high adsorption capacities of heavy metals Pb(II) and Cd(II).
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
·
IF 9.136
Xiang Li,Xueqian Wang,Langlang Wang,Li Yuan,Yixing Ma,Yibing Xie,Yiran Xiong,Ping Ning
The low S selectivity of catalysts for H 2 S removal significantly hinders its application in blast furnace gas desulfurization. In this study, Cu-based coconut shell biochar was modified with different types and contents of alkali species. The results showed that the S selectivity close to 100% was prolonged from 0 to 750 min. At the same time, the sulfur capacity was increased from 242.1 mg/g (before the modification) to 373.4 mg/g by using K 2 CO 3 -induced Cu-based biochar at 120 °C. In CO, H 2 O, and O 2 atmosphere, H 2 S was dissociated and oxidized to elemental S. Additionally, K 2 CO 3 exhibited an elemental S anchoring effect, making the S more stable at medium–high temperatures and weakening the reactivity of S with CO and ·O 2 – . Thus, less COS and SO 2 were generated. Moreover, the basic sites enhanced by K 2 CO 3 promoted the hydrolysis of COS to generate H 2 S, which entered the desulfurization cycle. K 2 CO 3 also showed a synergistic effect with the active components, generating more ·O 2 – to promote the oxygenation of H 2 S. The regeneration efficiency of the catalyst could be stabilized above 90%. These findings could provide guidance and reference for designing and applying desulfurization catalysts with high S selectivity and activity.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2025
·
IF 1.6
Zhang Yong,Liu Xuan,Jiang Kexing,Feng Jiaqi,Liu Yujia
In this study, peanut shell was used as the raw material to synthesize activated biochar-MnO composite (PSBC-K) using KMnO 4 as an activating agent. The Q max of U(VI) by PSBC-K was 569.8 mg/g, which was 3.9 times the Q max of PSBC (147.3 mg/g). Besides, PSBC-K exhibited good selectivity for U(VI) and excellent cycling performance. The removal mechanisms of U(VI) for PSBC-K were primarily dominated by electrostatic interaction, coordination reaction, precipitation and ion exchange. Overall, this work presented a sustainable and straightforward method for creating a novel adsorbent for efficient U(VI) separation.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2020
·
IF 5.715
Qibin Shen,Zhaoyue Wang,Qiao Yu,Yang Cheng,Zidan Liu,Taiping Zhang,Shaoqi Zhou
Biochar (BC) derived from Chinese herbal medicine residues has been investigated for its performance as a potential adsorbent in tetracycline (TC) removal. In the present study, a chemical co-precipitation method was carried out to prepare manganese dioxide modified biochar (Mn-BC) to increase its sorption capacity. The properties of the modified biochar were characterized for further enhancing TC removal from an aqueous solution. Mn-BC was successfully synthesized and resulted in a much higher specific surface area, total pore volume and pore diameter. The sorption kinetics of TC on Mn-BC was described by the pseudo-second-order model. The sorption data of Mn-BC were fitted by Langmuir and Freundlich models. The study findings revealed a maximum adsorption capacity of Mn-BC (1:10) to TC was up to 131.49 mg/g. The adsorption process was endothermic and spontaneous. The degradation of TC was further enhanced by MnO 2 acting as an oxidizer on Mn-BC. Overall, the modified biochar derived from Chinese herbal medicine residues is a superior alternative for the removal of TC from an aqueous solution.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Liying Jiang,Ke Li,Lingen Xia,Jiajun Gao,Lu Tang,Yanbo Jia
Hydrothermal carbonization (HTC) has been a promising treatment technology of heavy metal-enriched hyperaccumulator biomass to produce superior hydrochar adsorbent for contamination removal from the wastewater. However, a high amount of heavy metal in derived hydrochar limits its further application. In this study, the effect of reaction temperature (180–270 ℃) and medium pH during HTC on heavy metal contents, speciation and leaching risk of hydrochar from the hyperaccumulator biomass Sedum alfredii Hance was investigated to assess its environmental risk. HTC at a low reaction temperature and acid addition facilitated the removal of Zn/Cd/Pb from the solid phase, meanwhile the addition of acid favored the immobilization of Zn/Cd/Pb and lowered the potential leaching risk of Zn/Cd/Pb. Hydrochar prepared from HTC at 240 °C and pH = 2 had lower heavy metal content and lower releasing risk, followed by KOH modification to obtain high adsorption performance. The modified hydrohcar (KSAB) were characterized by SEM, XRD, BET, Boehm titration and FT-IR, and showed that the surface specific surface area and pore structure were optimized and OFGs of hydrochar were improved significantly after KOH treatment. Adsorption experiments showed that the Cd(II) adsorption process onto KSAB well accorded with pseudo-second-order kinetics and Langmuir isotherms. The maximum Cd(II) adsorption capacity of KSAB was 25.69 mg/g, which was 17 times compared to that of pristine hydrochar. Microstructure characteristics and mechanism analysis further suggested that electrostatic interactions, surface complexation, cation-π and ion exchange were the main Cd(II) removal mechanisms of KOH-modified hydrochar. Therefore, hydrochar derived from hyperaccumulator biomass can be used as a highly efficient absorbent to remove Cd(II) from wastewater after KOH modification.
研究领域:
环境科学
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污染治理
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2023
·
IF 11.4
Zepeng Liu,Jie Zhang,Liping Zhang,Ying Guan,Hao Ji,Yu Zhang,Hui Gao
Biochar (BC) prepared from Medulla Tetrapanacis was recognized as having potential in environmental remediation because of its porous texture, abundant chemical surface groups and mineral composition. In this study, a novel modified biochar (KBC) derived from Medulla Tetrapanacis achieved efficient adsorption of Congo red (CR) and methylene blue (MB). Characterization results suggested that the modification had little effect on the group distribution of KBC, but a dramatic expansion of specific surface area was observed on KBC (1180.45 m 2 /g) compared to BC (198.51 m 2 /g). KBC exhibited a maximum sorption of 584.17 mg/g for CR and 318.01 mg/g for MB. Kinetic and isotherm studies revealed sorption of CR and MB by KBC was chemosorption, which occurred on the monolayer surface. The comprehensive analysis also provided the basis for the application of KBC to practical production. These outcomes suggested that KBC may become a new option for the effluent treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2023
·
IF 7
Fuqiu Ma,Wenmin Zhu,Wanting Cheng,Jiaqi Chen,Jianzhang Gao,Yun Xue,Yongde Yan
In this study, the electrosorption property of potassium hydroxide modified activated carbon fiber felt (ACFF-KOH) to Co 2+ in simulated radioactive effluent was evaluated. Factors influencing the electrosorption such as applied voltage, initial concentration, pH, cyclic flow rate, competitive ions and cycle numbers on Co 2+ removal rate were investigated. Kinetic models and isotherm models were used to evaluate the electrosorption performance of ACFF-KOH. The results showed that the voltage enhanced the removal capacity of Co 2+ , which raised from 5.92 to 14.80 mg·g −1 when the applied voltage increased from 0 to 1.6 V. Higher initial concentration of the solution induced larger electrosorption capacity. In addition, the optimal adsorption pH of the electrosorption was around 5. When competing ions exist, the removal rate of Co 2+ decreased. Furthermore, ACFF-KOH had excellent cycling performance, and the removal rate remained above 85 % after 6 cycles. The pseudo-first-order (PFO) model fitted the data better than the pseudo-second-order (PSO) model, indicating that physisorption was the rate-limiting step during the eletrosorption process. A s the Langmuir isotherm had a higher regression coefficient (0.9983) than the Freundlich isotherm, monolayer adsorption was the main adsorption mechanism for Co 2+ on the ACFF-KOH electrode. The BET results showed that KOH modification improved the pore parameters of ACFF. According to the XPS and XRD results, Co(OH) 2 precipitates were generated on the electrode surface after electrosorption. The above results indicated that ACFF-KOH had excellent electrosorption and regeneration performance for Co 2+ in aqueous solution, thus it has great application value in the treatment of cobalt-containing radioactive effluent.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2023
·
IF 6
Yuting Wu,Yadong Wang,Peiao Chen,Yang Yang,Ziyue Tang,Yingquan Chen,Haigping Yang,Hanping Chen
In order to reduce nitrogen emissions during municipal sewage sludge (MSS) pyrolysis, the effects of co-pyrolysis of MSS with biomass and the second adsorption of KH 2 PO 4 -modified biochar were investigated. It was found that co-pyrolysis with cellulose inhibited the conversion of nitrogen into pyrolytic gas, and increased the N content in pyrolytic biochar. And the nitrogen fixation rate increased with cellulose addition increasing. Besides, compared with different biomass, MSS co-pyrolysis with 30% sugarcane bagasse had the optimal effect on nitrogen fixation (39%). Moreover, KH 2 PO 4 -modified biochar addition increased the second adsorption of nitrogenous volatiles and fixed nitrogen into oxides-N. The total nitrogen fixation rate reached maximum (47.65%) at 5% KH 2 PO 4 impregnation. Thus, it is an effective nitrogen fixation method that MSS co-pyrolysis of 30% sugarcane bagasse with the second absorption of 5% KH 2 PO 4 -modified biochar. This study provided an effective solution to improve the treatment of municipal sewage sludge by pyrolysis technology.
研究领域:
环境科学
·
能源与资源工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yongbiao Sun,Hui Li,Haijun Lai,Yan Yu,Meiling Hou,Chao Fu,Zaizhou Wang,Chunxiang Zhang
Natural gas purification before liquefaction necessitates the use of efficient adsorbents with high selective CO 2 adsorption and easy regeneration. Because of its efficiency and ease of operation, the ion exchange is widely employed to adjust zeolites’ CO 2 adsorption. However, few in-depth mechanistic studies have been undertaken on cation substitution regulation of pore structure and gas–solid interaction, as well as their synergistic effects on CO 2 selective adsorption and zeolite regeneration. In this study, we synthesized Li + and K + -modified 13X and examined their material characteristics, thermodynamics, adsorption kinetics, and the adsorption–desorption performance under various desorption methods. The results showed that the variation in pore structure and gas–solid interaction with cation radius is non-monotonic, resulting in 13XLi and 13XK having better CO 2 selective adsorption than 13X. All zeolites are extremely stable after 10 adsorption–desorption cycles in each regeneration setting. 13X outperforms 13XLi and 13XK in CO 2 desorption at 30 °C, owing to its large non-micropore volume and low gas–solid interaction. 13XK has the lowest CO 2 desorption rate at low temperature but the highest at high temperature, owing to the flat micropore distribution and the progressive gas–solid interaction. Approximately 100 % regeneration of 13XK is achieved with CH 4 purging (150 mL/min) at 150 °C, owing to its smallest cumulative pore volume at 0.5 nm. This research could help to develop efficient cation-modified X zeolites for CO 2 deep removal from CH 4 streams prior to liquefaction, as well as advance the in-depth understanding of cation substitution mechanisms.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Junhui Liu,Anfeng Zhang,Xiao Jiang,Min Liu,Jie Zhu,Chunshan Song,Xinwen Guo
Conversion of CO2 by hydrogenation into higher hydrocarbons has attracted much attention due to the continuous increasing concentration of CO2 in the atmosphere. Fe5C2 was used as the active site and mixed with K-modified supports for CO2 hydrogenation to synthesize value-added hydrocarbons. A series of supports were tested, and the alkaline Al2O3 was the best choice for light olefins and C5+ hydrocarbons. The transformation of product selectivity at time on stream demonstrated that potassium migrated into Fe5C2 during reaction. The selectivity of C2+ is 69.2% containing 35.8% C2–C4= and 29.1% C5+ value-added hydrocarbons with the 31.5% CO2 conversion (H2/CO2 = 3). When the ratio of H2 and CO2 was switched to 4, CO2 conversion improved to 40.9%, and the C2+ selectivity to 73.5%, containing 37.3% C2–C4= and 31.1% C5+ value-added hydrocarbons. The mixture catalysts can be directly used without any reduction before reaction, reducing the consumption H2 and simplifying the operation.
研究领域:
催化化学
·
能源化学
·
环境科学
·
材料化学
·
工业催化
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Ying Shi,Qiuming Zhou,Zhangfeng Qin,Zhiwei Wu,Weiyong Jiao,Mei Dong,Weibin Fan,Jianguo Wang
The aromatization of alkanes is an important process for improving the quality of Fischer-Tropsch synthesis (FTS) gasoline and producing high-valued aromatics from naphtha ; however, currently available catalysts in this regard are often deficient due to the low aromatics yield and short lifetime. In this work, a series of hierarchically structured Beta (Beta-HS) zeolites with high crystallinity and meso-porosity were synthesized by steam treatment with various organosilanes as pore-forming reagent and ethanol as solvent. The nano-sized Beta-HS zeolites were further modified with K through ion-exchange and with Pt through incipient wetness impregnation; the resultant Pt/K-Beta-HS catalysts were then used in the aromatization of n -heptane. The results indicate that the abundant mesopores present in Beta-HS are conducive to the diffusion of reactants and products, whilst the modification with K is able to passivate the strong Brønsted acid sites and the loading of Pt metal can promote the dehydrogenation of alkanes and cycloalkanes, which can effectively suppress the cracking and carbonaceous deposition reactions and enhance the dehydrogenation aromatization activity. As a result, the Pt/K-Beta-HS catalysts exhibit excellent performance in the aromatization of n -heptane, with a much longer lifetime (205 h), higher selectivity to aromatics (80%) and larger turnover number of aromatic products (Pt-based TON, 240 × 10 3 ) than conventional Beta zeolites. These results prove that the steam treatment with organosilanes as pore-forming reagent is a facile and cost-effective strategy to synthesize the hierarchically structured Beta zeolites and after loading K and Pt, the Pt/K-Beta-HS zeolites can be an efficient catalyst for the conversion of n -heptane to aromatics.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Zhicheng Xu,Yuran Li,Junxiang Guo,Jin Xiong,Yuting Lin,Tingyu Zhu
In this work and for the first time, an alkali metal potassium (K) as a promoter was loaded on an activated carbon (AC) to be used for selective catalytic reduction of NO from industrial flue gas. The denitrification activity of K-modified AC samples was investigated and compared with those of acid- and Cu-modified AC samples. The three modifications can enhance the denitrification activity of AC samples. To investigate the enhanced mechanisms of denitrification and SO 2 resistance, various AC samples were characterized by SEM, EDX, XRF, ICP, XRD, N 2 physisorption, H 2 -TPR, XPS, in situ DRIFTS and TPD. For the acid modification, the content of phenolic hydroxyl increases and then promotes the adsorption of NH 3 . For the loading of Cu, the appearance of Cu 2+ /Cu + sites with high catalytic activity promotes NH 3 and NO adsorption and changes the reaction pathway. For the loading of K, the adsorption capacity for NO increases nearly 12 times higher than that on Raw-AC, of which 85.0% is chemical adsorption. Moreover, three kinds of active nitrate species additionally forms, including nitro compounds, monodentate nitrate and nitrous oxide, which promote the denitrification reaction path. AC-Cu has poor sulfur resistance due to the sulfation of Cu, while AC-K show good sulfur resistance due to the enhanced adsorption of NO. The catalytic dissociation activity of N 2 O on AC-K makes the formation and decomposition of N 2 O into a dynamic equilibrium. As a result, AC-K has a high N 2 selectivity , while AC-Cu has poor N 2 selectivity.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）