INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2017
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IF 3.582
Shuang Ji,Zhourong Xiao,Haocui Zhang,Ling Li,Guozhu Li,Li Wang,Guozhu Liu
A high surface area (HSA) Ce 0.75 Zr 0.25 O 2 (CZ) support was synthesized by hydrothermal synthesis method with assistance of surfactant (cetyltrimethyl ammonium bromide , CTAB), and then 2.0 wt% Ru was impregnated on it to obtain a steam reforming catalyst for n-dodecane. The surface area of Ru/HSA-CZ catalyst is 107.6 m 2 g −1 , which is ca. three times higher than that prepared through the sol-gel (sg) method (34.3 m 2 g −1 , Ru/CZ-sg) and ca. 40% higher than that without CTAB (76.7 m 2 g −1 , Ru/CZ-wo). Catalytic steam reforming of n-dodecane, shows the completely conversion of n-dodecane over Ru/HSA-CZ and slightly drops about 6% (650 °C, LHSV = 12 mL/g h, S/C = 4, time on stream = 7 h) while 81% and 70% were observed for the Ru/CZ-wo and Ru/CZ-sg but with twice (or triple) deactivation rates. The possible reason for observed better performance of Ru/HSA-CZ should be attributed to the high metal dispersion of Ru over HSA-CZ, and the favorable Ru-support interaction as evidenced by H 2 -Temperature programmed reduction (H 2 -TPR), and high redox ability of high surface area Ce 0.75 Zr 0.25 O 2 support thanks to high Ce 3+ content. Further steam reforming of n-dodecane over Ru/HSA-CZ at higher LHSV (750 °C, LHSV = 36 mL/g h, S/C = 4) exhibits completed conversion and without significant deactivation.
研究领域:
化学工程
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催化材料
✓ 已验证
DOI
高影响因子
Biomass Conversion and Biorefinery
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2022
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IF 4.05
Chen Jiajia,Xiu Pengcheng,Gu Xiaoli
Lignin is the world’s greatest renewable aromatic biomass resource, with considerable potential for the development of high-value-added compounds. Herein, wet impregnation was employed to create Co-Mo/ATP-CZO bimetallic catalysts, which were then used to catalyze the depolymerization of lignin in ethanol and isopropanol. The findings of the characterization revealed that doping Mo metals resulted in the change of metallic oxide phase, which increased the oxygen vacancy (O V ), improved metal-carrier interaction, and decreased acid center content. The results of the experiments demonstrated that catalytic hydrogenation with a 12Mo-20Co/ATP-CZO catalyst at 240 °C for 8 h produced the maximum yield of bio-oil (57.44 wt%, including 37.58 wt% of monomer). Under these conditions, the bio-oil had a higher heating value of 33.20 MJ/kg, which was significantly higher than the alkali lignin’s 19.62 MJ/kg. Catalyst stability tests also revealed good recyclability. This research will provide an efficient method for depolymerizing lignin. Graphical abstract
研究领域:
能源化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2019
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IF 8.456
Liangbo Xie,Xueyue Mi,Yigang Liu,Yi Li,Yan Sun,Sihui Zhan,Wenping Hu
Polyacrylamide (PAM) in environmental water has become a major problem in water pollution management due to its high molecular mass, corrosion resistance, high viscosity, and nonabsorption by soil. The composite of Fe-doped Ce0.75Zr0.25O2 solid solution (Fe-Ce0.75Zr0.25O2) loaded on carbon felt (CF) was fabricated by a hydrothermal synthesis method, which was used as the cathode in a heterogeneous electro-Fenton system for the degradation of PAM. It showed that the degradation efficiency of PAM by the Fe-Ce0.75Zr0.25O2/CF cathode was 86% after 120 min and the molecular mass of PAM decreased by more than 90% after 300 min. Total organic carbon removal reached 78.86% in the presence of Fe-Ce0.75Zr0.25O2/CF, while the value was only 38.01% in the absence of Fe-Ce0.75Zr0.25O2. Further studies showed that the breaking of the chain begins with the amide bond, and then, the carbon chain was cracked into a short alkyl chain. As degradation progressed, both the complex viscosity and elasticity modulus of PAM solutions decreased nearly 50% at 300 min. It indicated that •OH were the most significant active species for the degradation of PAM. This novel Fe-Ce0.75Zr0.25O2/CF composite is an efficient and promising electrode for the removal of PAM in wastewater.
研究领域:
环境科学
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水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2014
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IF 6.007
Jun Yu,Zhichun Si,Lei Chen,Xiaodong Wu,Duan Weng
A zirconium phosphate @ Ce 0.75 Zr 0.25 O 2 (ZP/CZ) catalyst was synthesized by impregnating zirconium phosphates on Ce 0.75 Zr 0.25 O 2 microspheres. Catalysts with different structures were also synthesized by various methods to illustrate the structure advantage of ZP/CZ catalyst in selective catalytic reduction of NO x by ammonia (NH 3 -SCR). The catalysts were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), BET surface area, Infrared (IR) spectra, Ultraviolet-visible (UV–vis) spectroscopy, X-ray photoelectron spectroscopy (XPS), H 2 -temperature programmed reduction (TPR) and diffuse reflectance infrared Fourier transformed spectra (DRIFTS) of NH 3 /NO x adsorption. ZP/CZ catalyst presents excellent catalytic activity at 250–450 °C with a good N 2 selectivity under high space velocity of 300,000 h −1 . Firstly, the zirconium phosphate provides adsorption sites for ammonia on the surface of the catalyst and the cerium sites in the core act as the redox sites for NO oxidation. The pre-combination of zirconium and phosphate can reduce the strong interactions between phosphates and cerium ions. Therefore, the mobility of surface lattice oxygen on Ce 0.75 Zr 0.25 O 2 catalyst is retained, which is essential to obtain a catalyst with high NH 3 -SCR activity at low temperatures. Moreover, NH 4 NO 3 has proved to be an important intermediate for the NH 3 -SCR reaction on the surface of ceria based catalysts. The ZP/CZ catalyst preserves plenty of oxygen vacancies, facilitating the Ce 4+ → Ce 3+ redox circles and therefore promotes the nitrites/nitrates formation and desorption on catalyst. Two distinct adsorption sites for NH 3 and NO x result in a close contact between ads-NH 3 /NH 4 + and ads-NO 3 − /NO 2 − species on ZP/CZ catalyst, which can react with NO rapidly with the participation of active surface lattice oxygen.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2022
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IF 3.898
Jiajia Chen,Xinyu Lu,Dandan Wang,Pengcheng Xiu,Xiaoli Gu
Lignin is the world's greatest renewable aromatic biofeedstock, and it has promising applications in high value-added chemical products. Herein, N-Co/ATP-CZO was used as a catalyst for the depolymerization of alkali lignin in ethanol and isopropanol systems, and explored the effects of formic acid (FA) amount, reaction time, reaction temperature and other factors on the depolymerization of alkali lignin. Among them, formic acid serves as both catalytic and in situ-hydrogen donor. Ultimately, the highest yield of bio-oil (59.28% (mass)), including 30.05% (mass) of monomer , was obtained after a reaction of FA to alkali lignin mass ratio of 4 and 240 °C for 8 h. Among the monomers, the yield of Guaiacol was the highest (5.94% (mass)), followed by 2-methoxy-4-methylphenol (5.74% (mass)). This study, the modification of attapulgite was carried out to reduce the acidity while enhancing the catalytic activity for depolymerization, and the selection of hydrogen donor was investigated. A feasible pathway for lignin depolymerization research was opened.
研究领域:
化学工程
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可再生资源科学
✓ 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）