Search

Your search keyword '"Chen, Lungang"' showing total 326 results
Start Over Author "Chen, Lungang"
326 results on '"Chen, Lungang"'

120. Production of bio-jet fuel from corncob by hydrothermal decomposition and catalytic hydrogenation: Lab analysis of process and techno-economics of a pilot-scale facility

Author

Li, Yuping, primary, Zhao, Cong, additional, Chen, Lungang, additional, Zhang, Xinghua, additional, Zhang, Qi, additional, Wang, Tiejun, additional, Qiu, Songbai, additional, Tan, Jin, additional, Li, Kai, additional, Wang, Chenguang, additional, and Ma, Longlong, additional

Published
2018
Full Text
View/download PDF

130. One-Pot Hydrogenation of Furfural into Tetrahydrofurfuryl Alcohol under Ambient Conditions over PtNi Alloy Catalyst

Author

Wu, Jingcheng, Zhang, Xinghua, Chen, Qiang, Chen, Lungang, Liu, Qiying, Wang, Chenguang, and Ma, Longlong

Abstract

Furfural (FAL), a promising renewable platform compound from biomass, can be totally hydrogenated to an industrially important platform chemical, tetrahydrofurfuryl alcohol (THFA). In this work, a high yield of THFA was obtained by one-pot hydrogenation of FAL over a PtNi catalyst under mild reaction conditions. Small PtNi alloy particles were well distributed on active carbon. The catalysts were characterized by several physical–chemical technologies (transmission electron microscopy, X-ray diffraction, energy-dispersive spectroscopy, and inductively coupled plasma spectroscopy). Temperature-programmed reduction with hydrogen and in situ X-ray photoelectron spectroscopy demonstrate the presence of PtNi alloy. The electron-rich metal Pt could facilitate the heterolytic dissociation of hydrogen and promote the hydrogenation of FAL. Pt sites on the surface facilitate the adsorption at aldehyde (C═O) groups, and the furan ring strongly adsorbs on the Ni surface. Low reaction temperature is advantageous to reduce side reactions. Various metal concentrations were employed in this reaction; Pt(3)Ni(3)/C catalyst exhibits the best performance, achieving 99% FAL conversion and 93% THFA yield at 35 °C and under 2 MPa H2.

Published
2020
Full Text
View/download PDF

131. Manganese-Promoted Fe3O4Microsphere for Efficient Conversion of CO2to Light Olefins

Author

Jiang, Jiandong, Wen, Chengyan, Tian, Zhipeng, Wang, Yachen, Zhai, Yunpu, Chen, Lungang, Li, Yuping, Liu, Qiying, Wang, Chenguang, and Ma, Longlong

Abstract

In this work, manganese well-dispersed on Fe3O4microsphere (Mn–Fe3O4) catalyst was synthesized. It exhibited excellent catalytic performance for the direct conversion of carbon dioxide (CO2) into light olefins. A CO2conversion of 44.7% with high selectivity of light olefin (46.2%, yield of 18.7%), high O/P ratio (6.5), and low selectivity of CO (9.4%) was obtained over the 10Mn–Fe3O4catalyst. The Mn–Fe3O4catalyst was studied by XRD, SEM, (HR)TEM, STEM–EDS, H2-TPR, and CO2-TPD. The result indicated that the manganese promoter could facilitate the adsorption of CO2and the activation of C═O bonds as well as inhibit the secondary hydrogenation. This work offered a novel Fe-based catalyst system to the utilization of CO2and an understanding in promoting C═O bond activation in the first step of CO2hydrogenation to hydrocarbon reaction.

Published
2020
Full Text
View/download PDF

132. One-Pot Catalytic Conversion of Raw Lignocellulosic Biomass into Gasoline Alkanes and Chemicals over LiTaMoO6 and Ru/C in Aqueous Phosphoric Acid

Author

Liu, Yong, Chen, Lungang, Wang, Tiejun, Zhang, Qi, Wang, Chenguang, Yan, Jinyue, Ma, Longlong, Liu, Yong, Chen, Lungang, Wang, Tiejun, Zhang, Qi, Wang, Chenguang, Yan, Jinyue, and Ma, Longlong

Abstract

Lignocellulosic biomass is a renewable feedstock that has the potential to replace the diminishing fossil fuels. Herein, we reported the simultaneous conversion of cellulose, hemicellulose and lignin from raw biomass into gasoline alkanes (hexanes and pentanes) and monophenols and related hydrocarbons over layered LiTaMoO6 and Ru/C in aqueous phosphoric acid medium. Specifically, gasoline alkanes were directly yielded from the carbohydrate components, based on hemicellulose and cellulose, and the total yield could be up to 82.4%. Notably, the lignin fraction could also be transformed into monophenols, related alcohols and hydrocarbons by the one-pot reaction. It suggested that the hydrocracking of monophenol fraction could be performed in this catalytic system. The total yield of volatile products was 53% based on the lignin fraction. In this paper, the influences of phosphoric acid concentration, substrate ash and the amino acids derived from the biogenic impurities were investigated and different raw biomass substrates were tested. Furthermore, the catalysts could be reused for several runs to convert raw biomass without pretreatment., QC 20150917

Published
2015
Full Text
View/download PDF

139. Process and Techno-economic Analysis of Bio-jet Fuel-range Hydrocarbon Production from Lignocellulosic Biomass Via Aqueous Phase Deconstruction and Catalytic Conversion.

Author

Li, Yuping, Chen, Lungang, Zhang, Xinghua, Zhang, Qi, Wang, Tiejun, Qiu, Songbai, Tan, Jin, Li, Kai, and Ma, Longlong

Abstract

The integrated 1000 tonne/a-scale bio-jet fuel-range hydrocarbon (C 8 -C 15 ) synthesis system via aqueous phase deconstruction and catalytic conversion process was analyzed for its techno-economics of biomass residue utilization. The operation characterization, mass flow and cost in the system were discussed. A two-step deconstruction of corncob, steam stripping and acidic hydrolysis, was designed for the production of the platform chemicals, furfural and levulinic acid from hemicellulose and cellulose respectively. The oxygenate intermediates with the increased carbon chain length was produced by alkali catalyzed aldol condensation from furfural and levulinic acid. The oxygenate intermediates were catalytically converted to jet fuel-range hydrocarbon (C 8 -C 15 ) by the tandem steps of low-temperature hydrogenation, high-temperature hydrodeoxygenation and upgrading over noble metal catalysts. The results indicated that bio-jet fuel yield is 139 kg/h or 8 tonne of dried corncob for 1 tonne fuel production. The operation cost of bio-jet fuel is about $1540/tonne and the cost on corncob, catalytic catalyst and H 2 contributed 23%, 19% and 16% respectively. The cost sensitivity analysis showed that the catalytic lifetime was one of the main factors that affected the economics of bio-jet fuel production, which could increase bio-jet fuel price to $1820/tonne when its lifetime was reduced to 0.5 year. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

144. Efficient production of ethyl levulinate from cassava over Al2(SO4)3catalyst in ethanol–water system

Author

Tan, Jin, Liu, Qiying, Chen, Lungang, Wang, Tiejun, Ma, Longlong, and Chen, Guanyi

Abstract

One-pot achievement of ethyl levulinate from cassava was conducted in ethanol–water system over several simple sulfate salt catalysts. Al2(SO4)3catalyst had the best performance in synthesizing ethyl levulinate comparing with those of a series of sulfate salts. The highest yields of ethyl levulinate was up to 39.27% as well as 7.78% levulinate acid when cassava was catalyzed in ethanol medium by adding 10wt% water. 13C and 1H NMR spectroscopic investigations confirmed that isomerization of glucose to fructose over Al2(SO4)3catalyst is an important step in producing ethyl levulinate and levulinate acid. Due to aggregations of Al3+under hydrothermal conditions, tiny amount of Al3+were detected in filtrate at the percentage of 0.32% even if in absolute water. Brønsted and Lewis acids could improve the yield of ethyl levulinate and levulinate acid by synergistic effect. All results suggested that Al2(SO4)3was a simple and efficient catalyst for ethyl levulinate and levulinate acid production.

Published
2017
Full Text
View/download PDF

148. Ru–MnOxInteraction for Efficient Hydrodeoxygenation of Levulinic Acid and Its Derivatives

Author

Liu, Yong, Gu, Canshuo, Chen, Lungang, Zhou, Wenguang, Liao, Yuhe, Wang, Chenguang, and Ma, Longlong

Abstract

Metal–oxide interaction was widely observed in supported metal catalysts, playing a significant role in tuning the catalytic performance. Here, we reported that the interaction of Ru and MnOxwas able to facilitate the hydrodeoxygenation of levulinic acid (LA) to 2-butanol with a high turnover frequency (1.99 × 106h–1), turnover number (4411), and yield (98.8%). Moreover, this catalyst was capable of removing the hydroxymethyl group of lactones and diol with high yields of products. The high activity of the Ru–MnOxcatalyst was due to the strong Ru–MnOxinteraction, which facilitated reduction of Ru oxide to Ru0and Mn oxide to Mn2+. The increased fractions of Ru0and Mn2+provided metal and Lewis acid sites, respectively, and therefore facilitated LA hydrodeoxygenation. A linear correlation between the hydrodeoxygenation activity of the Ru–MnOxcatalyst and [Mn2+]ln([Ru0]) was observed.

Published
2023
Full Text
View/download PDF

149. Aqueous-phase hydrodeoxygenation of propanoic acid over the Ru/ZrO2 and Ru–Mo/ZrO2 catalysts

Author

Chen, Lungang, Zhu, Yulei, Zheng, Hongyan, Zhang, Chenghua, and Li, Yongwang

Subjects
*OXYGENATION (Chemistry), *PROPIONIC acid, *CATALYSTS, *HYDROGEN, *ZIRCONIUM oxide, *PRESSURE
Abstract

Abstract: The conversion of propanoic acid under high hydrogen pressure has been studied over zirconia-supported monometallic Ru and bimetallic Ru–Mo catalysts. The cleavage of C–C bond of propanoic acid to methane and ethane is improved and the formation of Cnation products (propanol and propane) is decreased with increasing the temperature. Upon addition of Mo, both the overall activity and the C–C bond cleavage selectivity decrease while the selectivity of Cnation increases. With increase of Mo contents, the C–C bond cleavage reaction is significantly inhibited, especially at high temperature. This is also confirmed by the DRIFTS of propanoic acid, showing that the propanoyl intermediate species on Ru–Mo bimetal catalysts is more difficult to dissociate to CO compared with Ru monometal catalyst. Based on H2-TPR, CO-FTIR and DRIFTS of propanoic acid characterizations, the reaction mechanisms and the resulting selectivity towards the possible reaction paths (C–C bond cleavage/Cnation) are discussed in terms of the formation of Ru–MoO x and the stability and variety of propanoyl intermediate species occurring on the Ru–Mo bimetal catalysts. It is suggested that the interaction of Ru and MoO x species and the formation of Ru–MoO x interface are the important factors for the decrease in the TOF of propanoic acid and the C–C bond cleavage selectivity. [Copyright &y& Elsevier]

Published
2012
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results