Molecular Catalysis
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2024
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IF 3.9
Jianfu Luan,Jiayou Liu,Xiaoxiang Huang,Zhongchao Tan,Hesheng Yu
The NH 2 -MIL-125 (NM-125) or modified NM-125 materials are used for photocatalytic removal of nitric oxide (NO). Most researchers attributed few NO 2 emission during NO photocatalysis to high selectivity towards the formation of nitrate ions due to the neglect of the principle of electroneutrality and pore structure of NM-125. This may cause misleading photocatalytic mechanism of NO removal. Herein, this work proposes a new mechanism behind NO removal using NM-125 based on experimental investigations and theoretical calculations. First, experimentally, the highest NO removal efficiency of 88.54 % with negligible NO 2 emission occurs at the anhydrous condition. In addition, in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements verify the presence and accumulation of NO 2 as product during photocatalytic conversion of NO. Furthermore, density functional theory (DFT) calculations and grand canonical Monte Carlo (GCMC) computations demonstrate that there exist strong interactions between NO 2 and -NH 2 group within pores. Few NO 2 is detected during experiments is probably due to its subsequent adsorption in the pores of NM-125. The new NO removal mechanism including photocatalytic conversion NO into NO 2 and subsequent NO 2 adsorption in the pores of NM-125 is thus proposed. This work provides a deeper insight into photocatalytic NO removal over NM-125 and its variants.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2017
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IF 2.843
Yi Zhao,Han Wang,Siqi Hao
Molecularly imprinted polymers (MIP1 and MIP2) were synthesized using acrylamide as the functional monomer and acetic acid and ethanedioic acid as the template, respectively. Textural properties of MIPs and nonimprinted polymer (NIP) were characterized by an N2 adsorption experiment, thermogravimetric analysis, and Fourier transform infrared spectroscopy. NO2 basic adsorption conditions were set as 40 °C for the temperature, 100 mL/min for the flow rate, and 1000 ppm for the NO2 concentration through fixed-bed breakthrough experiments, and at these conditions, the NO2 adsorption capacity of MIP1, MIP2, and NIP was 0.58, 0.63, and 0.51 mg/g, respectively. The NO2 adsorption performance was nearly unaffected by O2; however, SO2 and CO2 inhibited NO2 adsorption severely. The H2O molecule had fewer negative effects on NO2 adsorption because of the large number of hydrophobic groups −(CH2–CH)n– in polymers and the hydrogen bond force between H2O molecules.
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
Journal of Cleaner Production
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2021
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IF 9.297
Aamir Hanif,Mingzhe Sun,Tianqi Wang,Shanshan Shang,Daniel C.W. Tsang,Jin Shang
NO 2 is a potent air pollutant because of its deleterious effects on human beings and other organisms. The state-of-the-art catalysis-based deNO x techniques (e.g., selective catalytic/non-catalytic reduction) are incapable of ambient NO 2 abatement due to their low efficiency at temperatures below 300 °C. It is thus conceivable to directly capture NO 2 from the atmosphere by selective adsorption on porous materials. This work reports the rational development and demonstration of the Mg–Al layered double hydroxides (LDHs) and their derived mixed metal oxides (MMO), using environmentally benign solvents , as high-capacity adsorbents for ambient NO 2 abatement. By boosting the densities of accessible basic sites using layer delamination strategies, the highest NO 2 adsorption capacity of 8.52 mmol/g was achieved by the delaminated LDH material (LDH-AM), which was substantially higher than other popular and robust adsorbents, such as zeolites (0.36–3 mmol/g) and carbon-based adsorbents (2–6 mmol/g). Using Fourier transform infrared spectroscopy and powder X-ray diffraction, it was revealed that NO 2 adsorption occurs on the surface M-OH basic sites and within the layers by simultaneously replacing the interlayer CO 3 2− ions of LDH. This work affords not only promising, durable, and scalable adsorbents for ambient NO 2 removal but also a strategy to develop adsorbents with high density of basic sites for capture of other pollutant acid gases from the environment.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Shanshan Shang,Chao Yang,Yuanmeng Tian,Zeyu Tao,Mallory Smith,Hongyan Zhang,Lin Zhang,Liangchun Li,Qinfen Gu,Hong-Cai Zhou,Yong Sik Ok,Jin Shang
Selective adsorption using porous materials is a promising approach to removing ambient nitrogen dioxide (NO 2 ). However, the highly reactive nature of NO 2 and the often-associated release of nitric oxide (NO) render a formidable challenge in developing effective and stable adsorbents. Here, we designed multivariate porphyrin-based metal–organic frameworks (MTV-PMOFs Al-PMOF(Ni x Co y )) featuring atomically dispersed Ni/Co dual-metal centers in the porphyrin ring as active adsorption sites, as robust adsorbents capable of synergistically boosting NO 2 adsorption capability and retaining the evolved NO. The introduction of the Ni/Co dual-metal sites in MTV-PMOFs greatly enhanced the NO x adsorption performance. Under dry conditions, Al-PMOF(Ni 1 Co 1 ) exhibited a NO 2 adsorption capacity of 3.66 mmol/g (100 ppm NO 2 in feed), among the highest under similar conditions, a high NO retention ability, and good regenrability (85%). Under wet conditions, its NO 2 removal capacity was further elevated by more than 50% (5.65 mmol/g). Moreover, the Ni/Co ratio in MTV-PMOFs dictates a structure–property relationship between the released amount of NO and adsorbed capacity of NO 2 . Such a corporative NO 2 and NO adsorption was for the first time established in MOFs. The material stability and potential economic value were also investigated to demonstrate the applicability of MTV-PMOFs as NO 2 adsorbents. This work provides new perspectives for the development of adsorption-based technology for mitigating ambient NO 2 pollution and managing other corrosive and toxic gases.
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
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