Gas Science and Engineering
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2025
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IF 5.5
Chenyang Lin,Yijun Wang,Yihang Liu,Takeshi Hagio,Baowen Zhou,Xinling Li,Zhen Huang
Direct air capture (DAC) is a technology that captures low concentrations of CO 2 directly from the air. In recent years, amine-modified solid adsorbents have been widely utilized to facilitate an efficient CO 2 capture process. In industrial applications, the significant pressure drop reduced by powder accumulation results in economic losses for fans. However, previous studies on monoliths have failed to simultaneously satisfy the industrial requirements for both adsorption capacity and mechanical strength. In this work, a novel honeycomb monolith was proposed to address this issue. The seven uniformly distributed channels effectively reduced pressure drop, while the wall thickness satisfied the mechanical strength requirements under industrial application conditions. And the structure was optimized by using activated carbon. After high-temperature treatment, the new pore formed in the space previously occupied by the activated carbon. Through the secondary loading approach, the amine loading was comparable to the powder. Compared with the monoliths without activated carbon, the pore volume significantly increased (from 5.31 % to 96.26 %). The pore volume of 20AC-SiO 2 -M reached 0.84 cm 3 g −1 . At 35 °C and 400 ppm, 20AC-SiO 2 -M exhibited the best CO 2 adsorption capacity (1.94 mmol/g) and the fastest CO 2 adsorption rate (0.0395 mmol/(g.min)). Additionally, the structure strength (1.46 MPa) and pressure drop losses (0.002 psi) were tested, and both parameters met the requirements for industrial applications.
研究领域:
环境科学
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材料科学
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化学工程
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吸附分离
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碳捕集与封存
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2021
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IF 5.909
Xiangyu Li,Zhiqing Wang,Ru Feng,Jiejie Huang,Yitian Fang
If a large amount of fly ashes produced by coal-fired power plants was not treated harmlessly, it will pose a serious threat to the ecological environment. As one of the high-valued utilization technologies of fly ash, the technology of extracting aluminum from coal ash produces large quantities of waste residue after acid leaching nevertheless. It is an economic and environmentally friendly way to recycle alumina-extracted residue (AR) as solid sorbent to capture CO 2 . In this study, using AR as raw material, we synthesized PEI modified solid sorbents by novel “wet gel impregnation” method (WGI) to enhanced CO 2 capture. The effects of amine loading, adsorption temperature, and impregnation method on CO 2 adsorption capacity and kinetics were investigated by thermogravimetric analysis (TGA). On this basis, a possible double-layer adsorption model was proposed, i.e., the PEI adsorption layer on the outer surface of sorbents and the internal isolation layer. The ratio of the two layers changed with the variation in PEI loading and adsorption temperature, resulting in the difference of adsorption capacity. The maximum CO 2 adsorption capacity of 2.07 mmol/g was obtained under the amine loading of 40 wt% at 95 °C, and 100% CO 2 . Moreover, the stable adsorption capacity and high CO 2 selectivity were maintained in five repeated adsorption-desorption cycles.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
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2025
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IF 10
Tong Xu,Xiaopei Ding,Chengcai Li,Haoyang Cheng,Guojin Liu,Hailin Zhu,Yuhai Guo,Xueliang Jiang,Jiuming Li
Accelerated industrial expansion has led to significant wastewater pollution, with effluent containing the toxic heavy metal Cr(VI) posing severe threats to ecosystems and human health. The combination of metal-organic frameworks (MOFs) and membrane separation techniques offers promising solutions for pollutant removal. This study developed a polytetrafluoroethylene (PTFE)-based composite membrane for effective Cr(VI) removal from aqueous solutions. This membrane was prepared through the in-situ synthesis of zinc-zirconium bimetallic MOFs on a PTFE membrane that had been modified with L-DOPA/PEI. The composite membrane demonstrated optimal Cr(VI) adsorption at a Zr:Zn molar ratio of 1:4, under conditions of 45 °C and pH = 2, with a maximum adsorption capacity of 335.1 mg/g. The adsorption process of Cr(VI) onto the composite membrane adhered to both the pseudo-second-order kinetic model and the Freundlich adsorption isotherm. Thermodynamic analyses confirmed a spontaneous, endothermic process. The composite membrane, with its excellent adsorption capacity, filtration performance, and recyclability, stands out as a highly effective material for the removal of Cr(VI) from aqueous solutions. Furthermore, it addresses the issues of aggregation, difficulty in separation, and the recycling challenges associated with powder-like MOFs, demonstrating significant potential for practical applications.
研究领域:
环境科学
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材料工程
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水处理
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Qingdi Kong,Xiaojie Zhang,Kangrui Ma,Yuefa Gong,Hong Peng,Wei Qi
It is a challenging task to remove heavy metal ions efficiently from the wastewater containing high concentrations of complexants. In this work, a novel PEI-modified chitosan/activated carbon composite adsorbent (PCA) was prepared and applied to the removal of Cu(II) from pyrophosphate plating rinsing wastewater. The main species of Cu(II) in the pyrophosphate wastewater was [Cu(HP 2 O 7 ) 2 ] 4− or [Cu(P 2 O 7 ) 2 ] 6− , which were denoted as [Cu(II)-PP] anions. The maximum adsorption capacity of PCA for Cu(II) reached 1.41 mmol g −1 under the condition of pH = 8 and molar ratio of pyrophosphate to Cu(II) = 4:1. The adsorption kinetic behavior of Cu(II) on PCA followed the Elovich model best and PCA attained adsorption equilibrium within 36 h. The thermodynamic studies showed that the adsorption process of Cu(II) by PCA was endothermic and spontaneous. The PCA fixed bed column was used to remove Cu(II) from simulated pyrophosphate plating rinsing wastewater. After three consecutive adsorption-desorption cycles, the adsorption performance, hydraulic conductivity , and mechanical stability of PCA column did not decrease. The FTIR and XPS analysis results indicated that [Cu(II)-PP] anions can be adsorbed on PCA by electrostatic attraction with protonated amine groups or coordination with the amine groups of PCA via ligand substitution.
研究领域:
环境科学
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水处理
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材料科学
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
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