CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Yongsheng Jia,Donghang Chen,Yan Li,Enze Li,Long Zhao,Limin Guo
In this study, CO 2 was converted to activated carbon by the molten salt CO 2 capture and electrochemical conversion (MSCC-EC) method, and the surface oxygen content of the activated carbon was further modified for the adsorption of polar molecules (chlorobenzene) and nonpolar molecules (toluene), the role of the pore structure and surface O-containing functional groups of the adsorbents in contributing to the adsorption process was systematically investigated. The results showed that MS-AC 500-10 , MS-AC 500-15 , and MS-AC 550-15 have rich pore structures with specific surface areas of 811.56 m 2 /g, 835.35 m 2 /g, 1249.104 m 2 /g, and surface oxygen contents of about 10 %, 15 %, 15 %, respectively. The toluene adsorption capacity of MS-AC 500-10 , MS-AC 500-15 , and MS-AC 550-15 was 203.82 mg/g, 229.72 mg/g, and 358.97 mg/g, respectively, and was dominated by pore adsorption, which was positively proportional to the specific surface areas and pore volumes, the adsorption process belonged to the pseudo-first-order kinetic model. The adsorption amounts of chlorobenzene by MS-AC 500-10 , MS-AC 500-15 , and MS-AC 550-15 were 287.98 mg/g, 363.11 mg/g, and 495.41 mg/g, respectively. In addition to the pore adsorption, the oxygen content on the surface of the adsorbents had a non-negligible promotion effect on the adsorption of chlorobenzene, mainly because chlorobenzene is a polar molecule, and the asymmetric electrons on its surface have strong interactions with the O-containing functional groups on the surface of the adsorbents. Moreover, the prepared adsorbents were thermally stable, and the decay rate of adsorption performance was less than 5 % after five adsorption–desorption cycles.
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
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Peng Hu,Xiaopeng Liang,Muhammad Yaseen,Xiaodan Sun,Zhangfa Tong,Zhongxing Zhao,Zhenxia Zhao
A novel mechano-chemical strategy using dopamine to modify UiO-66(Zr) by N-coordination was proposed to enhance its competitive adsorption for acetaldehyde, chlorobenzene/H 2 O, both thermodynamically and kinetically. The newly synthesized material was characterized by SEM, EDX, XPS, PXRD, FT-IR, TGA/DTG and BET techniques. Results showed that N was successfully grafted into UiO-66(Zr) frameworks through coordination interaction with Zr-O clusters resulting in M-UiO-66(Zr-N 3.0 ). The obtained M-UiO-66(Zr-N 3.0 ) exhibited a significant increase in adsorption of chlorobenzene (4.94 mmol/g) and acetaldehyde (9.42 mmol/g) compared to parent UiO-66(Zr) and UiO-66(Zr)-NH 2 . The H 2 O adsorption uptake of M-UiO-66(Zr-N 3.0 ) decreased by 20% that of UiO-66(Zr) and 47% of UiO-66(Zr)-NH 2 indicating higher hydrophobicity of the modified material. Kinetic performance indicated that diffusivity of chlorobenzene on M-UiO-66(Zr-N 3.0 ) was about 7.8 and 40 times higher than that of the parent UiO-66(Zr) and UiO-66(Zr)-NH 2 respectively and 15.4 times higher than that of H 2 O on itself. Based on the results, the current N-modification strategy can be deemed as an efficient way to improve MOFs competitive adsorption towards VOCs under humid conditions and it might play active role in industries involving adsorbent applications.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Wei Zhao,Yinan Xu,Yuehui Qiao,Rui Sun,Jie Qian,Yixue Wang,Quan Liu,Zhekun Shi,Fandong Meng,Xiaoli Zhan,Qinghua Zhang
Zeolites have been widely utilized in the adsorption of volatile organic compounds (VOCs) due to their high specific surface area and robust stability. However, the adsorption capacity of zeolites for VOCs is considerably reduced under humid conditions due to the competitive adsorption between water and VOCs, thereby limiting their industrial applicability. Herein, we report a core–shell ZSM-5@NiAl-LDH (Z-L) composites designed specifically for efficient adsorption of VOCs under high humidity conditions. The core–shell architecture is achieved by introducing active sites onto the ZSM-5 framework pretreated with high-alkalinity agents, followed by the growth of NiAl-LDH on its surface, creating a regular, vertically staggered structure. Compared with ZSM-5 zeolite, Z-L composites show a larger specific surface area, wider pore size, and larger mesopore volume, allowing a high adsorption capacity of the VOCs. Contact angle and static adsorption tests of water molecules reveal that the LDH shell effectively increases the hydrophobicity of Z-L composites. The dynamic adsorption behavior for m-xylene demonstrates that Z-L composites exhibit significantly enhanced adsorption capacity, 3.79 times that of ZSM-5 zeolite. Furthermore, Z-L composites exhibit a higher selectivity for m-xylene at 60 % relative humidity, achieving a Q wet /Q dry ratio of 86.7 %, outperforming most porous adsorption materials. Kinetic model analysis reveals that the augmentation of mesopores in Z-L composites enhances the effective diffusion space for synthesized samples, resulting in exceptional adsorption performance. This novel synthetic material is anticipated to be a promising candidate for VOCs pollution control in high-humidity environments.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2023
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IF 5.2
Qiang Yu,Wenna Zhang,Junjie Li,Wen Liu,Yanan Wang,Weifeng Chu,Xinbao Zhang,Longya Xu,Xiangxue Zhu,Xiujie Li
Although FAU zeolites have been widely used as absorbents for volatile organic compounds (VOCs) removal, preparation of high-silica FAU zeolite to expand its application under high humidity is still a big challenge. Here, two high-silica FAU zeolites were successfully prepared through the controllable framework modulation strategy. By carefully matching the degrees of dealumination and Si-insertion, the zeolite (FAU-H) with an ultra-high SiO 2 /Al 2 O 3 ratio of 957 was obtained. FAU-H exhibited similar high adsorption capacities of VOCs (e.g. m-xylene and toluene) under dry and humid conditions, more importantly, its adsorption capacity of m-xylene was 25% higher than the industrial high-silica FAU zeolite (HSZ-390HUA) from Tosoh Corporation. When the dealumination degree was mismatched with that of Si-insertion, imperfect FAU-M (SiO 2 /Al 2 O 3 = 108) with the existence of some defect sites was obtained that becomes a good candidate for the adsorption removal of small VOCs molecules (e.g. isopropanol). The moderate interaction between VOCs and zeolite framework is proved a key factor for small molecules adsorption on basis of the DFT calculations. Moreover, the fitted kinetic models, desorption tests, and adsorption−desorption cycling tests proved the good regenerability of FAU-H and FAU-M. Therefore, the proposed high-silica FAU zeolites are promising adsorbents for VOCs removal.
研究领域:
材料科学
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环境工程
·
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）