CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Hongyu Niu,Xing-Bao Wang,Jingjie Luo,Jiaxin Liu,Chuang Li,Wen-Ying Li,Changhai Liang
Desulfurization plays a critical role in refining crude oil to produce fuel and the manufacture of fine chemicals. However, its low efficiency becomes a great challenge for the present desulfurization if only the C-S cleavage is considered a promising approach to reducing hydrogen consumption under atmospheric pressure. Accordingly, we investigate the critical factors necessary to achieve high C-S cleavage of dibenzothiophenes under mild conditions of 0.1 MPa and H 2 /oil = 100. The mechanism of reactive adsorption desulfurization of dibenzothiophenes with or without steric hindrance at atmospheric pressure on Pt/ZnO is proposed by studying the adsorption model of active metal sites, the Pt efficiency in C-S cleavage influenced by the steric hindrance and the structural evolution of Pt active centers in the presence of sulfur adsorption/deposition. Based on both experimental and DFT results, we report C-S cleavage of dibenzothiophenes with (TOF = 15 h −1 ) or without steric hindrance (TOF = 128 h −1 ) that can be highly efficiently fractured (99.9%) by the interface between PtS x and ZnO . This work has great practical significance for developing atmospheric industrial adsorbents for ultra-deep reactive adsorption desulfurization.
研究领域:
化学工程
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催化材料
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能源化工
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Coal Preparation and Utilization
·
2023
·
IF 2.1
Xuexia Wang,Wencheng Xia,Yaoli Peng,Guangyuan Xie
Iron-assisted pyrolysis (Fe-assisted pyrolysis) is a high-efficiency technique to remove sulfur from low-rank coal. However, the sulfur removal mechanism of Fe-assisted pyrolysis did not compressively address. For filling this gap, this study explored the sulfur removal mechanism of diphenyl sulfone during Fe-assisted pyrolysis based on the factor optimization of desulfurization performance. The iron powder under the optimal conditions of Fe-assisted pyrolysis was characterized with X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS), showing that FeS and some FeS2 were formed on the surface of post-pyrolysis iron powder. Gas chromatography (GC) analysis manifested that the addition of iron powder in the pyrolysis process could considerably reduce the SO2 emission. GC and Fourier transform infrared spectrometer (FTIR) analyses demonstrated that there was C–S bond broken in the diphenyl sulfone structure during Fe-assisted pyrolysis. From the results of thermogravimetry-mass spectrometry (TG-MS), the addition of iron powder in the pyrolysis process could enhance the reaction rate and reduce the temperature required for the reaction. We believe that the results of the present study provided a theoretical basis for a profound understanding of the desulfurization mechanism of Fe-assisted pyrolysis.
研究领域:
能源科学
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2020
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IF 4.335
Nian Zheng,Ce Liu,Ya-Nan Ding,Wei-Yu Shi,Bo-Sheng Zhang,Yong-Min Liang
Copper-catalyzed three-component redox-neutral ring opening of benzothiazoles with aryl iodides and O-benzoyl hydroxylamines for the synthesis of 1-amino-N-(2-(phenylthio)phenyl)methanimine has been developed. This one-pot reaction undergoes C–S and N–O bond cleavage and new C–S and C–N bond construction. Several control experiments excluded a free radical procedure and also demonstrated the secondary amine as a possible intermediate, which was vital to the catalytic reaction. Meanwhile, the deuteration experiment got rid of the C–H activation dehydroisomerization of the benzothiazole mechanism.
研究领域:
有机化学
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合成化学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Fanjing Wei,Xiaoxia Zhang,Junjie Liao,Jiawei Guo,Weiren Bao,Liping Chang
The reactive adsorption desulfurization mechanism of thiophene over Cu/ZnO sorbent in coke oven gas (COG) was established by a combination of theoretical and experimental study. The adsorption behavior of thiophene on Cu surface was studied by density functional theory (DFT) method. The C 4 hydrocarbons releases and sulfur migration over Cu/ZnO sorbent during the thiophene removal process were investigated by comparing with that over CuO, ZnO and CuO+ZnO (prepared by mechanical grinding of CuO and ZnO) sorbents. The results show that the parallel adsorption of thiophene on hexagonal closest packing (HCP) site of Cu (1 1 1) crystal face is the optimal adsorption mode. Cu 0 nanoparticles in Cu/ZnO sorbent have two important roles: (1) adsorb and dissociate H 2 , and (2) cleave the C–S bond of thiophene. The sulfur after the cleavage of C–S bond could transfer directly to ZnO and eventually be converted into ZnS without the intermediate product CuS. During thiophene removal, C 4 H 6 and C 4 H 10 are generated over Cu/ZnO sorbent in the presence of H 2 . ZnO in Cu/ZnO sorbent not only acts as an excellent sulfur accepter, but can greatly affect the adsorption properties by enhancing the spillover and storage of hydrogen atoms . Increasing the interaction between Cu 0 nanoparticles and ZnO to enhance hydrogen spillover is an effective way to improve the thiophene reactive adsorption activity of Cu/ZnO.
研究领域:
化学工程
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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
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Xiangzhuo Han,Yingchao Zhang,Jinkai Wang,Zhanchen Cui,Zuosen Shi
Sulfonate oxime ester photoinitiators (PIs) based on a thioether-substituted 1,8-naphthalenedicarboximide backbone exhibit good absorption at the emission wavelengths of commonly used LED lamps (385, 395, and 405 nm). The presence of weak C–S and N–O bonds in the molecular structure enables them to be cleaved under light, which leads to the generation of free radicals and cations with efficient initiation properties. Electron paramagnetic resonance spectroscopy supports the mechanism of C–S bond cleavage to produce free radicals, and UV–visible real-time spectroscopy in the presence of Rhodamine B base supports the mechanism of N–O bond cleavage to produce acids. These compounds are high-performance photoinitiators without any other additives for the polymerization of double-bonded compounds and epoxides. They can be initiated at low concentrations when exposed to UV-LEDs. These photoinitiators provide important ideas for the design and synthesis of photoinitiators, which have great potential for application in the field of photopolymerization, especially in hybrid light-curing systems.
研究领域:
材料科学
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光化学
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聚合物科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2017
·Vol. 83
·期 23
·
IF 3.807
Cui-Wei Chu,Bin Liu,Na Li,Shi-Gang Yao,Dan Cheng,Jia-Dong Zhao,Ji-Guo Qiu,Xin Yan,Qin He,Jian He
Thiobencarb is a thiocarbamate herbicide used in rice paddies worldwide. Microbial degradation plays a crucial role in the dissipation of thiobencarb in the environment. However, the physiological and genetic mechanisms underlying thiobencarb degradation remain unknown. In this study, a novel thiobencarb degradation pathway was proposed in Acidovorax sp. strain T1. Thiobencarb was oxidized and cleaved at the C—S bond, generating diethylcarbamothioic S-acid and 4-chlorobenzaldehyde (4CDA). 4CDA was then oxidized to 4-chlorobenzoic acid (4CBA) and hydrolytically dechlorinated to 4-hydroxybenzoic acid (4HBA). The identification of catabolic genes suggested further hydroxylation to protocatechuic acid (PCA) and finally degradation through the protocatechuate 4,5-dioxygenase pathway. A novel two-component monooxygenase system identified in the strain, TmoAB, was responsible for the initial catabolic reaction. TmoA shared 28 to 32% identity with the oxygenase components of pyrimidine monooxygenase from Agrobacterium fabrum, alkanesulfonate monooxygenase from Pseudomonas savastanoi, and dibenzothiophene monooxygenase from Rhodococcus sp. TmoB shared 25 to 37% identity with reported flavin reductases and oxidized NADH but not NADPH. TmoAB is a flavin mononucleotide (FMN)-dependent monooxygenase and catalyzed the C—S bond cleavage of thiobencarb. Introduction of tmoAB into cells of the thiobencarb degradation-deficient mutant T1m restored its ability to degrade and utilize thiobencarb. A dehydrogenase gene, tmoC, was located 7,129 bp downstream of tmoAB, and its transcription was clearly induced by thiobencarb. The purified TmoC catalyzed the dehydrogenation of 4CDA to 4CBA using NAD+ as a cofactor. A gene cluster responsible for the complete 4CBA metabolic pathway was also cloned, and its involvement in thiobencarb degradation was preliminarily verified by transcriptional analysis.IMPORTANCE Microbial degradation is the main factor in thiobencarb dissipation in soil. In previous studies, thiobencarb was degraded initially via N-deethylation, sulfoxidation, hydroxylation, and dechlorination. However, enzymes and genes involved in the microbial degradation of thiobencarb have not been studied. This study revealed a new thiobencarb degradation pathway in Acidovorax sp. strain T1 and identified a novel two-component FMN-dependent monooxygenase system, TmoAB. Under TmoAB-mediated catalysis, thiobencarb was cleaved at the C—S bond, producing diethylcarbamothioic S-acid and 4CDA. Furthermore, the downstream degradation pathway of thiobencarb was proposed. Our study provides the physiological, biochemical, and genetic foundation of thiobencarb degradation in this microorganism.
研究领域:
环境微生物学
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分子生物学
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生物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
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2020
·Vol. 142
·期 3
·1287-1294
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IF 2.731
Wang Jiawei,Sui Zifeng,Zheng Yifei,Wang Tao,Zhang Yongsheng,Xu Hong,Pan Wei-Ping
As one of the technologies for the improvement in coal quality, biological enzyme technology has received much attention. The enzyme product named 3EC was shown to enhance the power plant performance in our previous full-scale test. In this work, its effect on coal was explored. The results indicated that the enzyme product was beneficial in the removal of organic sulphur from coal, and the catalytic action of 3EC on the cleavage of C–C and C–S bonds was proven based on data from the dibenzothiophene decomposition test. Thus, when it was used to treat coal, the CH 3 -to-CH 2 ratio changed from 0.81 to 0.32 with an increase in treatment time, which indicated that some chemical structures in the enzyme-treated coal changed. Because of these structural changes, the combustion behaviour of coal improved, indicated by the increase in the comprehensive combustion index from 2.958 × 10 6 to 3.113 × 10 6 % 2 min −2 K −3 and the decrease in activation energy from 32.76 to 30.43 kJ mol −1 . In addition, the optimum enzyme treatment time should be 4 days to ensure enough reaction time between the enzyme and the coal.
研究领域:
能源与燃料
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 96
·93260-93266
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IF 3.289
Jianxiong Wang,Fan He,Yonghong Li,Hongwei Sun
Experiments and quantum chemistry calculations were performed to study the decomposition mechanism of isopropylthiobenzene, the role of supercritical water (SCW) and the effects of alkanes on the decomposition of isopropylthiobenzene. In this study, three possible decomposition paths in SCW were described. The most feasible decomposition path involves four steps. First, hydrocarbon radicals attack the α-H on the isopropyl group of isopropylthiobenzene, leading to cleavage of one C–S bond to form thioacetone. Second, a cycloaddition of water to thioacetone occurs to form a mercaptoalcohol. Third, mercaptoalcohol decomposes into H2S and acetone either directly or via the catalysis of water. Finally, acetone decomposes into CO2 via free radical reactions. During the decomposition process, SCW partakes mainly as an H-transfer catalyst and a reactant by forming a n-membered ring transition state (n = 4, 6). The alkanes cause selective cleavage of the C–S bond and promote desulfurization by forming free radicals. In addition, isopropyl from isopropylthiobenzene could act in the same way as an alkane to promote the decomposition of isopropylthiobenzene in SCW.
研究领域:
化学工程
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物理化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Mingshuo Chi,Jianpeng Cui,Jianwen Hu,Junjie Fan,Senchang Du,Peiwen Xiao,Songqing Hu,Shuangqing Sun
The enhancement of heavy oil recovery and the promotion of oil-water separation are crucial aspects of fossil fuel resource development. In this study, silica Janus nanosheets were prepared and anchored with Ni nanoparticles for in-situ upgrading and stimulus-responsive demulsification of heavy oil. The results of aquathermolysis reactions revealed that Ni/Ph-SiO 2 -Ni/P4VP Janus nanosheets exhibited excellent characteristics in reducing heavy oil viscosity by 98.49 %, and 99.52 % with the addition of a hydrogen donor. FT-IR, 1 H NMR and GC, etc. analysis of the oil samples indicated that Ni/Ph-SiO 2 -Ni/P4VP breaks the C-S bond and reduces the content of the resin, asphaltene , polycyclic aromatics, and long chain alkanes in the oil. Moreover, it can stabilize heavy oil emulsions in an acidic medium (pH = 2) and separate oil and water in a neutral medium (pH = 7) due to its stimulus-responsive performance. This work highlights the potential application of Ni/Ph-SiO 2 -Ni/P4VP Janus nanosheets for the in situ upgrading and stimulus-responsive demulsification of heavy oil.
研究领域:
材料科学
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化学工程
·
石油工程
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纳米技术
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环境科学
✓ 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）