CHEMOSPHERE
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2017
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IF 4.208
Hongyun Hu,Dunkui Chen,Huan Liu,Yuhan Yang,Hexun Cai,Junhao Shen,Hong Yao
Arsenic emission from fuel combustion and metal smelting flue gas causes serious pollution. Addition of sorbents is a promising way for the arsenic capture from high temperature flue gas. However, it is difficult to remove arsenic from SO 2 /HCl-rich flue gas due to the competitive reaction of the sorbents with arsenic and these acid gases. To solve this problem, arsenic adsorption over γ-Al 2 O 3 was studied in this work to evaluate its adsorption mechanism, resistance to acid gases as well as regeneration behavior. The results show that γ-Al 2 O 3 had good resistance to acid gases and the arsenic adsorption by γ-Al 2 O 3 could be effectively carried out at a wide temperature range between 573 and 1023 K. Nevertheless, adsorption at higher-temperature (like 1173 K) leaded to the decrease of surface area and the rearrangement of crystal structure of γ-Al 2 O 3 , reducing the active sites for arsenic adsorption. The adsorption of arsenic was confirmed to occur at different active sites in γ-Al 2 O 3 by forming various adsorbed species. Increasing temperature facilitated arsenic transformation into more stable chemisorbed As 3+ and As 5+ which were difficult to remove through thermal treatment regeneration. Fortunately, the regeneration of spent γ-Al 2 O 3 could be well performed using NaOH solution.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
APPLIED ENERGY
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2018
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IF 7.9
Xiaowen Zhang,Rui Zhang,Helei Liu,Hongxia Gao,Zhiwu Liang
To enhance the energy efficiency of the CO 2 desorption process, the regeneration behaviors of the CO 2 -loaded 6 M MEA-AMP-PZ (monoethanolamine, 2-amino-2-methyl-1-propanol and piperazine) tri-solvent blends with different AMP/PZ molar ratios with four different solid acid catalysts (H-ZSM-5, γ-Al 2 O 3 , SAPO-34 and SO 4 2− /TiO 2 ) and a blank at 96 °C were investigated in terms of CO 2 desorption rate, cyclic capacity and relative heat duty. For the no-catalytic runs, the results showed that all the tri-solvent blended amines greatly increased CO 2 desorption rate, cyclic capacity and decreased the relative heat duty in comparison with 5 M MEA. The 13 C NMR analysis indicated that the 3 M MEA-2.5 M AMP-0.5 M PZ blend with the highest AMP/PZ ratio produced the largest amount of bicarbonate and less carbamate, which resulted in the best desorption performance. With regard to catalyst, when the solid acid catalysts were introduced, the regeneration performance of the blend was further improved. The best of the blends along with H-ZSM-5 provided the combination with the best performance in CO 2 desorption, and reduced the relative heat duty by 61.6% as compared to 5 M MEA without catalyst (100%). Five relevant physicochemical properties of the catalyst were obtained and used to better understand the catalytic regeneration process. A possible catalytic CO 2 desorption mechanism was analyzed. The results revealed that the mesopore surface area coupled with total acid sites of the catalyst had the most positive influence on improving the CO 2 desorption performance. Findings from this work imply that the combination of solid acid catalyst with tri-solvent blended amines is a promising alternative method for further reduction of solvent regeneration energy requirement.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
Minerals
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2025
·Vol. 15
·期 8
·772
·
IF 2.2
Jingchao Li,Yide Xu,Tingting Chen,Yijun Cao,Guixia Fan
The structural memory effect is normally considered one of the most important properties of LDHs. However, certain anions can have adverse effects on it. In this study, three types of CLDHs (Mg2Al1-CLDH, Mg2Al0.5Fe0.5-CLDH, Mg2Fe1-CLDH) were obtained and used to observe their regeneration behaviors in the presence of sulfate, silicate, and phosphate, respectively, at initial pH values of 10 and 13. The samples were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA-DTG), scanning electron microscope (SEM), and N2 adsorption–desorption isotherm (BET). The results suggested that silicate and phosphate have significant impacts on the regeneration of CLDHs, while sulfate does not. Specifically, phosphate and silicate reacted with MgO to generate magnesium silicate and magnesium phosphate dibasic, which were covered on the surface of particles and hindered the hydroxylation of metal oxides. However, a higher pH can suppress the formation of new substances and promote the regeneration of LDHs. Moreover, the CLDHs with high specific surface area had a stronger anti-interference performance regarding the effects of phosphate and silicate.
研究领域:
无机化学
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材料化学
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环境化学
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纳米材料
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吸附与界面科学
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2023
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IF 9.5
Qiang Zhang,Tianze Xie,Xizhen Yi,Gaowa Xing,Shuo Feng,Shulang Chen,Yuxuan Li,Jin-Ming Lin
Confinement of chemical species in a controllable micrometer-level (several to a dozen micrometers) space in an aqueous environment is essential for precisely manipulating chemical events in subcellular regions. However, rapid diffusion and hard-to-control micrometer-level fluids make it a tough challenge. Here, a versatile open microfluidic method based on an aqueous two-phase system (ATPS) is developed to restrict species inside an open space with micron-level width. Unequal standard chemical potentials of the chemical species in two phases and space-time correspondence in the microfluidic system prevent outward diffusion across the phase interface, retaining the target species inside its preferred phase flow and creating a sharp boundary with a dramatic concentration change. Then, the chemical flow (the preferred phase with target chemical species) is precisely manipulated by a microfluidic probe, which can be compressed to a micron-level width and aimed at an arbitrary position of the sample. As a demonstration of the feasibility and versatility of the strategy, chemical flow is successfully applied to subcellular regions of various kinds of living single cells. Subcellular regions are successfully labeled (cytomembrane and mitochondria) and damaged. Healing–regeneration behaviors of living single cells are triggered by subcellular damage and analyzed. The method is relatively general regarding the species of chemicals and biosamples, which could promote deeper cell research.
研究领域:
生物技术
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细胞生物学
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微流控
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化学生物学
✓ 已验证
DOI
PubMed
高影响因子