CHINESE JOURNAL OF CATALYSIS
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2019
·
IF 4.914
Kang Kong,Difan Li,Wenbao Ma,Qingqing Zhou,Guoping Tang,Zhenshan Hou
Glycerol is a by-product of biodiesel production and is an important readily available platform chemical. Valorization of glycerol into value-added chemicals has gained immense attention. Herein, we carried out the conversion of glycerol to formic acid and glycolic acid using H 2 O 2 as an oxidant and metal (III) triflate-based catalytic systems. Aluminum(III) triflate was found to be the most efficient catalyst for the selective oxidation of glycerol to formic acid. A correlation between the catalytic activity of the metal cations and their hydrolysis constants ( K h ) and water exchange rate constants was observed. At 70 °C, a formic acid yield of up to 72% could be attained within 12 h. The catalyst could be recycled at least five times with a high conversion rate, and hence can also be used for the selective oxidation of other biomass platform molecules. Reaction kinetics and 1 H NMR studies showed that the oxidation of glycerol (to formic acid) involved glycerol hydrolysis pathways with glyceric acid and glycolic acid as the main intermediate products. Both the [Al(OH) x ] n + Lewis acid species and CF 3 SO 3 H Brønsted acid, which were generated by the in-situ hydrolysis of Al(OTf) 3 , were responsible for glycerol conversion. The easy availability, high efficiency, and good recyclability of Al(OTf) 3 render it suitable for the selective oxidation of glycerol to high value-added products.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2019
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IF 7.723
Habib Ullah,Bibimaryam Mousavi,Hussein A. Younus,Zafar A.K. Khattak,Suleman Suleman,Muhammad T. Jan,Baoyi Yu,Somboon Chaemchuen,Francis Verpoort
Carbon dioxide , the main cause of environmental pollution, its utilization to produce valuable products is of utmost interest. A series ONO pincer hydrazone based most active mono-nuclear Al(III) complexes were successfully synthesized and characterized with the help of NMR, IR, mass spectrometry and only complex 2a was confirmed by single-crystal analysis. The synthesized Al(III) complexes were then employed as capable catalysts for the solvent-free chemical fixation of CO 2 with epoxides at atmospheric pressure and could be reused five times without loss of any catalytic activity. In addition, the catalytic mechanism was investigated by analyzing intermediates via 1 H NMR, 13 C NMR, and mass MALDI-TOF. The excellent catalytic performance could be due to simultaneous attack and the opening of the epoxide by metal centers to form an alkoxide ion which activates the CO 2 the same time.
研究领域:
化学
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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
ADVANCED FUNCTIONAL MATERIALS
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2019
·Vol. 29
·期 29
·1902079
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IF 15.621
Guangjun Zhang,Xiaopeng Xu,Young Woong Lee,Han Young Woo,Ying Li,Qiang Peng
Two novel perylene diimide (PDI)–based derivatives, Alq 3 -PDI and Alq 3 -PDI 2, are synthesized by flanking a 3D tri(8-hydroxyquinoline)aluminum(III) (Alq 3 ) core with PDI and a helical PDI dimer (PDI2) to construct high-performance small molecular nonfullerene acceptors (SMAs). The 3D Alq 3 core significantly suppresses the molecular aggregation of the resulting SMAs, leading to a well-mixed blend with a PTTEA donor polymer and weak phase separation. Compared with Alq 3 -PDI , the extended π-conjugation of Alq 3 -PDI2 results in higher-order molecular packing, which improves the absorption and phase separation behavior. Thus, the Alq 3 -PDI2 devices have higher J sc and FF values and better device performance, which are further enhanced by a small amount of 4,4′-bipyridine (Bipy) as an additive. The coordination between Bipy and the Alq 3 core promotes molecular packing and phase separation, which lower charge recombination and enhanced charge collection in the resulting devices. Therefore, a largely improved J sc of 15.74 mA cm −2 and very high FF of 71.27% are obtained in the Alq 3 -PDI2 devices, resulting in a power conversion efficiency of 9.54%, which is the best value reported for PDI-based polymer solar cells. The coordination can also serve as a “molecular lock,” which prevents molecular motion and thus improves device stability.
研究领域:
材料科学
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有机光电子学
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太阳能电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Zihan Qin,Yuzhen Wang,Liang Sun,Yuanxiang Gu,Yan Zhao,Lei Xia,Yang Liu,Bart Van der Bruggen,Yang Zhang
Industrial applications and environmental awareness recently prompted vanadium recovery spell from secondary resources. In this work, a polymer inclusion membrane containing trioctylmethylammonium chloride as carrier was successfully employed in electrodialysis for vanadium recovery from acidic sulfate solutions. The permeability coefficient of V(V) increased from 0.29 µm·s -1 (without electric field) to 4.10 µm·s -1 (with the 20 mA·cm -2 current density) . The transport performance of VO 2 SO 4 - , which was the predominant species containing V(V) in the acidic region (pH <3), was influenced by the aqueous pH value and sulfate concentration. Under an electric field, a low concentrated H 2 SO 4 solution (0.2 M) effectively stripped V(V) from the membranes, avoiding the requirement of a highly concentrated H 2 SO 4 without electric field. Under the optimum conditions, the permeability coefficient and flux reached 6.80 µm·s -1 and 13.34 µmol·m -2 ·s -1 , respectively. High selectivity was observed for the separation of V(V) and Mo(VI) from mixed solutions of Co (II), Ni (II), Mn (II), and Al (III). Additionally, the separation between Mo(VI) and V(V) was further improved by adjusting the acidity of the stripping solution. The V(V) selectivity for the resulting membrane was higher than that of commercial anion exchange membranes.
研究领域:
环境工程
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材料科学
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化学工程
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电化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2015
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IF 6.723
Qiao An,Zifeng Li,Robert Graff,Jia Guo,Haifeng Gao,Changchun Wang
A hydrid microsphere Fe3O4@carbon@poly(InIII-carboxylate) consisting of a cluster of Fe3O4 nanoparticles as the core, a carbon layer as the inner shell and a porous InIII–carboxylate coordination polymer as the outer shell was prepared and applied as a recyclable catalyst for the cycloaddition reaction of CO2 and epoxides. Construction of this hybrid microsphere was achieved in the two steps, including (1) the one-pot solvothermal synthesis of Fe3O4@C particles with the abundant carboxylic groups on the carbon surface and (2) the subsequent growth of the outer shell polymers based on the precipitation coordination polymerization. Imidazolium-substituted Salen ligands were synthesized and chelated with the In(III) ions using the terminal carboxylic groups. The coordination polymer shell was formed on the Fe3O4@C particles, and the structures including shell thickness, surface area and porosity could be varied by tuning the feeding ratios of the In(III) ions and the ligands. The optimal structure of the coordination polymers showed a shell thickness of ca. 45 nm with ∼5 nm of mesopore, 174.7 m2/g of surface area and 0.2175 cm3/g of pore volume. In light of gas uptake capability, catalytic activity and magnetic susceptibility, cycloaddition of CO2 with a series of epoxides were studied by using Al-complexed Fe3O4@C@InIII-[IL-Salen] microspheres. The results validated that the self-supporting catalytic layer with high surface area was of remarkable advantages, which were attributed from great increment of effective active sites and combination of nucleophilic/electrophilic synergistic property and CO2 uptake capability. Therefore, these hybrid microspheres provided excellent catalytic activity, prominent selectivity to cyclic carbonates and outstanding recyclability with the assistance of an applied magnetic field.
研究领域:
材料科学
·
化学工程
·
催化
·
纳米技术
·
环境化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）