CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Yi Liu,Shuangjiang Li,Ying Chen,Mengrui Li,Zewen Chen,Tianding Hu,Lan Shi,Manoj Pudukudy,Shaoyun Shan,Yunfei Zhi
The development of highly efficient and metal- and halogen-free heterogeneous catalysts for the chemical conversion of CO 2 to cyclic carbonates plays a critical role in the reduction of greenhouse gas emissions. Herein, two melamine-based organic polymers namely UM-OP and AM-OP with abundant N sites and –NH- groups were synthesized by a facile method and their activity for cycloaddition of CO 2 with epoxides was investigated. The structural analysis shows that the UM-OP and AM-OP catalysts were composed of specially designed urea and amide group linkages, respectively. UM-OP and AM-OP are metal-free, halogen-free, and can efficiently catalyze CO 2 cycloaddition under solvent-free and cocatalyst-free conditions. Moreover, the UM-OP catalyst exhibited higher catalytic activity than AM-OP, good structural stability, recyclability, separability from the products, and shown high activity to a series of epoxides. The density functional theory (DFT) calculations revealed the activation of epoxides by –NH- groups and CO 2 by N sites in the samples, respectively, and N sites can also act as nucleophiles to realize ring opening of epoxides. Combining the results of experiments and calculations, it was further found that the double –NH- (urea group) is more efficient than single –NH- (amide group) to activate the epoxides. This paper reveals the mechanism of N sites and –NH- groups synergistically catalyzing the CO 2 cycloaddition, and further supports the theory that N atoms acts as nucleophile for ring opening, providing a reference for the design of metal- and halogen-free heterogeneous catalysts.
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APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Zhipeng Liu,Chang Liu,Jiawei Zhang,Suhua Mao,Xiao Liang,Hanlin Hu,Xiaoxi Huang
Layered materials have been investigated in many different catalytic reactions due to their excellent functionalities. In particular, understanding the anisotropic properties of layered materials is important for the design of more efficient catalysts. Herein, SnS 2 nanoflakes with abundant edge sites (E-SnS 2 ) were synthesized and their catalytic properties towards the electrochemical CO 2 reduction reaction (CO 2 RR) were studied. Combining experimental data and computational analysis, we found that the edge sites of SnS 2 are more active for CO 2 to formate conversion compared with the basal sites. Moreover, a CO 2 reduction intermediates triggered activation mechanism at the edge sites is proposed, the formation of sulfur vacancies at the edges would generate more active sites for CO 2 RR. The as-synthesized E-SnS 2 shows high selectivity, activity and robust stability for at least 12 h in a flow cell under a current density of − 200 mA·cm -2 . This work may provide a new perspective on rational catalyst design for CO 2 RR.
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FUEL
·
2023
·
IF 7.4
Peng Li,Senlin Zhang,Zhourong Xiao,Hui Zhang,Fei Ye,Jianmin Gu,Jidong Wang,Guozhu Li,Desong Wang
Catalytic reduction of CO 2 to high value-added chemicals such as methane is crucial in the development of renewable energy and waste disposal. Photo-thermal CO 2 methanation has been received great attention, because the synergistic effect of photo and thermal lead to efficient CO 2 reduction at low temperature. Herein, we reported the synthesis of Ni nanoparticles (NPs) supported on TiO 2 (Ni-TiO 2 ) derived from MIL-125 (Ti-MOFs) for photo-thermal CO 2 methanation. The nanoparticle sizes and electron densities of metallic Ni, defects and chemical properties, photo-thermal and photo-electric characteristics of the catalysts have been systematically characterized by XRD, TEM, CO 2 /H 2 -TPD, XPS, photoluminescence and photocurrent. For the Ni-TiO 2 , the conversion of CO 2 was 56 % under the full spectrum irradiation (1200 mW/cm 2 ) at 325 °C, which was about 1.8 times of that without light irradiation. The selectivity of methane nearly 99 % with a production rate was 95.7 mmol/(g cat ∙h), which was about 2.7 times of that without light irradiation. Meanwhile, the catalysts showed excellent stability without any activity decay during the four cycles testing (32 h). The main reasons for the high catalytic performance for photo-thermal CO 2 methanation were attributed to the uniform distribution of Ni NPs with synergistic effect of large specific surface area of TiO 2 with abundant moderate strength alkaline sites. In addition, good photo-thermal and photo-electric conversion ability make the catalysts possess more photo-generated charge carriers and reduce its recombination.
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高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2021
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IF 8.528
Bozhen Wu,Fa-Qian Liu,Shu-Wen Luo,Liu-Qin Zhang,Fangxin Zou
A new three-dimensional (3-D) interconnected elastic scaffold with high thermal conductivity was prepared from hydroxylated graphene (HG) and hydroxylated carbon nanotubes (HCNTs). Then, polyethyleneimine (PEI) was uniformly covalently grafted to the surfaces of the scaffold, to give a HG-HCNTs-PEI nanocomposite as a superior CO 2 adsorbent. The resulting nanocomposites possess high amine loading (9.46 mmol N g −1 ) and high adsorption capacity in simulated flue gas (up to 4.43 mmol CO 2 g −1 ). Due to the excellent thermal conductivity (5.1 W/mK), the adsorbents exhibit superior cyclic stability even in harsh desorption temperature (135 °C), Thus, these carbonaceous materials-supported adsorbents make the CO 2 capture process practical and promising.
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APPLIED SURFACE SCIENCE
·
2021
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IF 6.707
Xiaohan Yang,Hanbin Liu,Liwei Qian,Qingjun Meng,Haiwei Wu,Zhijian Li,Hongwei Zhou
The remediation of water that polluted by organic dyes and nanoparticles (NPs) remains a great challenge. However, second pollution of solid waste may produce if the adsorbents are not degradable or recyclable. The stimuli-responsive materials were regarded to be able to resolve this problem by reversible adsorption-desorption under stimuli. Here in this work, the surface of cellulose fibers was modified with CO 2 -responsive molecules through a simple esterification followed by an aza-Michael addition reaction. The chemical structure was confirmed with Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), x-ray diffractometer (XRD) and thermal analysis. The gas-responsiveness was demonstrated by monitoring of the pH, conductivity and surface zeta potential. Anionic dyes and negative charged NPs in water can be selectively and reversibly captured by the CO 2 -responsive surface on cellulose fibers, suggesting the inexpensive, readily available and smart cellulose fibers may find great potential in water remediation.
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高影响因子
ACS Sustainable Chemistry & Engineering
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2021
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IF 8.198
Xiaochen Xu,Jie Dong,Xian Xiao,Xin Zhao,Qinghua Zhang
At present, the glassy polymeric membrane technology for CO2 separation is still confronted with a predicament that it is still difficult to fabricate membranes with both high CO2 permeance and high gas selectivity. Fortunately, newly developed thin film composite membranes (TFC) (∼100 nm) can facilitate high CO2 permeation by minimizing gas trans-membrane resistance and macrovoid defects. Herein, a novel TFC membrane containing a thin polyimide (PI) selective layer on a PDMS-modified PSf substrate was successfully constructed in situ by an interfacial cross-linking reaction between the amine-end-capped PI oligomer and the trimesoyl chloride (TMC) in a mild solvent system. The thickness of the thin PI selective layer is in the range of 103–485 nm and can be optimized by adjusting the interfacial polymerization parameters such as the TMC concentration. The resultant TFC membrane comprising a polyimide selective layer exhibits an optimum CO2 permeance of 330 GPU with the CO2/N2 and CO2/CH4 ideal selectivities of 30 and 32, respectively. It is an obvious improvement in CO2 separation performance compared with conventional PI flat membrane. In addition, these membranes also show an excellent plasticizing resistance and long-term stability attributed to the cross-linking structure and thin nature. It is expected that this TFC membrane structure combined with its facile fabricating process can facilitate the development of thin glassy polymeric membranes for CO2 separation.
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Sustainable Energy & Fuels
·
2021
·Vol. 5
·期 24
·6449-6459
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IF 6.367
Zhige Zhang,Guofeng Zhao,Han Bing,Jiawei Zhong,Haoran Yuan,Jun Xie,Yong Chen
The efficient utilization of renewable biogas has attracted ever-increasing interest in the past few decades. Ni–Ce1−xZrxO2 supported on monolithic SiC-F (named Ni–Ce1−xZrxO2/SiC-F) is developed and applied in biogas reforming. Monolithic Ni–Ce1−xZrxO2/SiC-F catalysts were comprehensively characterized by ICP-AES, XRD, SEM, HR-TEM, CO2-TPD, etc. The promotional roles of Ce1−xZrxO2 in coke elimination as well as CO2 activation were deeply analyzed via in situ CH4-TPSR/CO2-TPO and in situ H2-TPR/CO2-TPSR. Ni–Ce1−xZrxO2/SiC-F exhibits satisfactory catalytic activity and ability to inhibit sintering and coke-deposition due to (a) the homogeneous dispersion of Ni nanoparticles (NPs) and (b) the strong interaction between Ce1−xZrxO2 solid solutions and Ni NPs. At 900 °C and a weight hourly space velocity (WHSV) of 24 000 mL gcat−1 h−1, an excellent CH4/CO2 conversion of 90/92% was initially achieved over the Ni–Ce1−xZrxO2/SiC-F catalyst, followed by a slight decrease after 150 h, but remained basically stable for the next 250 h.
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Molecular Catalysis
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2021
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IF 5.062
Xin Wang,Lei Shi,Yanglin Chen,Chaokun Yang,Li Yang,Jianmin Sun
With the aim of green chemistry and sustainable development, the coupling of CO 2 with epoxides to cyclic carbonate is an attractive and promising CO 2 fixation without byproducts. Solvent- and metal-free heterogeneous catalysts offer an environmentally friendly and convenient separation alternative to traditional metal-based or homogeneous catalysts. Hence, hydrolyzed carbon nitride (HCN) was successfully synthesized via urea-derived carbon nitride (CN) hydrolyzed in NaOH solution and the freeze-drying (FD) method was adopted to obtain the HCN-FD catalyst. The composition and chemical properties of HCN-FD were thoroughly characterized by different analysis methods. The synergistic effects of hydrogen-bond donors of –COOH, –OH and –NH X in HCN-FD resulted in improved acidity sites characterized by NH 3 -TPD. Compared with CN, HCN-FD combined with tetrabutylammonium iodide cocatalyst displayed satisfactory catalytic performance in the CO 2 cycloaddition due to more exposed active sites (–COOH, –OH and –NH X ). Moreover, the recyclability and versatility of the HCN-FD catalyst were excellent in CO 2 cycloaddition reaction. Thus, the HCN-FD catalyst was a potential candidate for the practical utilization of CO 2 fixation due to its advantage of facile synthetic method, inexpensive raw material and environmental friendliness.
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JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
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2021
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IF 4.346
Qi Wu,Yan Xu
Stimulus-responsive surfactant is becoming a hot research topic with high controllability and excellent emulsifying properties. In this work, an amidine naphthenate surfactant was synthesized for the first time by the reaction between alkyl amidine and naphthenic acid. Surface activity and emulsion performance of this novel surfactant in oil/water emulsion were investigated. Compared with the previously synthesized amidine bicarbonate surfactants, amidine naphthenate surfactants exhibited a superior emulsification performance above 60 °C due to their lower critical micelle concentration (CMC) and interfacial tension (IFT). The presence of two long alkyl groups is recognized as the main reason for its superior properties than amidine bicarbonate having only one long alkyl group. Increased hydrophobic interactions between the long alkyl chains and electrostatic interactions between the ionic head groups lead to the easier formation of micelles. Notably, the amidine naphthenate has a characteristic of CO 2 -responsive property. The amidine naphthenate emulsion can be demulsified by CO 2 bubbling which destroys the chemical structure of amidine naphthenate, accompanied by the formation of amidine cations and naphthenic acids. Then, the emulsion was completely demulsified due to the demulsification effect of naphthenic acid. Therefore, the synthesized amidine naphthenate surfactant possesses not only high interface activity but also CO 2 responsive property, which endows it an extensive application prospect for enhanced oil recovery (EOR) operations in the oil industry.
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Greenhouse Gases-Science and Technology
·
2021
·Vol. 11
·期 6
·1191-1197
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IF 2.013
Subrato Acharjya,Jiacheng Chen,Minghui Zhu,Chong Peng
Immobilized tin phthalocyanine dichloride (SnPcCl 2 ) was prepared by refluxing SnPcCl 2 and hydroxyl-functionalized carbon nanotubes in DMF with the addition of triethylamine, which exhibited minimal aggregation and approximately 2–3 folds improvement in activity towards CO 2 electroreduction compared to the physically mixed SnPcCl 2 /CNT hybrid. Cyclic voltammetry analysis and in situ UV-vis spectra revealed that metallic tin is the active site for CO 2 electroreduction, and the redox behavior of Sn 0 is affected by the adjacent demetallized macrocycles. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.
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ChemSusChem
·
2021
·Vol. 14
·期 8
·1962-1969
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IF 8.928
Yanling Qiu,Wenbin Xu,Pengfei Yao,Qiong Zheng,Huamin Zhang,Xianfeng Li
Graphical A helping hand : Copper electrodes derived from Cu 2 O with predominant (111) facets are synthesized by cetyltrimethylammonium bromide-assisted preparation. The optimized electrode shows a high faradaic efficiency of 90 % for formic acid obtained by electrochemical reduction of CO 2 at −2.0 V (vs.SCE), which surpasses most reported Cu electrodes. The electrochemical reduction of CO 2 (ERC) to valuable chemicals has attracted extensive attention. However, the relatively low selectivity and efficiency of the reaction remain challenges. In this study, Cu electrodes derived from Cu 2 O with predominant (111) facets are synthesized by cetyltrimethylammonium bromide-assisted preparation. The optimized electrode shows a high faradaic efficiency of 90 % for HCOOH obtained by ERC at −2.0 V (vs.SCE), which surpasses most reported Cu electrodes. Based on a comprehensive analysis of the relationship between the catalytic activity and the thickness of the Cu 2 O layer, the catalytic activity of the unit active site on the Cu 2 O-derived Cu electrodes is found to be higher than that on the blank Cu electrode. DFT calculations indicate that OCHO* would be produced preferentially over *COOH in the presence of cetyltrimethylammonium bromide (CTAB). This deduction is verified by testing of the effects of CTAB and KBr addition on HCOO − selectivity.
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PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
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IF 13.273
Xiaoqian Li,Dechao Wang,Zhongjie He,Fangfang Su,Nan Zhang,Yangyang Xin,Hongni Wang,Xiaolu Tian,Yaping Zheng,Dongdong Yao,Mingtao Li
Porous liquids (PLs) as a novel class of materials combine the permanent porosity of microporous solids, the rapid mass transfer of liquids, and fluidity, thus exhibiting extraordinary promise for gas capture and separation. However, the practical application of PLs was severely restricted by their undesirable relative high viscosity and melting temperature. In this work, the symmetric dicationic ionic liquids [C 6 BIm 2 ][NTf 2 ] 2 was synthesized as a steric hindrance solvent to construct a type of low viscosity zeolitic imidazolate frameworks (ZIFs)-based PLs. Specifically, the ZIF-67-PLs-2 ( i.e. , ZIF-67 loading of 2.0% in PLs) presented a low viscosity with 543.4 mPa·S at 25 °C, which was about 20 times lower than that of type III PLs reported previously. Meanwhile, ZIF-67-PLs showed long-term stability even over 180 days and broke the fluidity limitation down to −64 °C, broadening the work conditions. Moreover, ZIF-67-PLs-10 ( i.e. , ZIF-67 loading of 10.0% in PLs) achieved 55 times CO 2 and 7 times toluene adsorption capacity more than those of the corresponding pure DILs, respectively. Remarkably, the fascinating features of ZIF-67-PLs including lower viscosity, wide liquid range and higher adsorption pave a new way for the optimal design of novel PLs towards gas uptake and separation.
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危险品化学品经营许可证（带存储）