INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2018
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IF 4.229
Long-Fei Xie,Pei-Gao Duan,Jia-Li Jiao,Yu-Ping Xu
A series of Ni catalysts with different zeolites were prepared by wet impregnation method and used to catalyze supercritical water gasification (SCWG) of microalgae for production of hydrogen-rich fuel gas under conditions of 430 °C, 60 min, ρ H₂O = 0.162 g/cm 3 , 2 g/g Ni/zeolites. Compared with noncatalytic SCWG, the presence of Ni/zeolite could increase the hydrogen gasification efficiency and carbon gasification efficiency by promoting water–gas shift and steam reforming reactions which are mainly affected by the amount of strong acid sites and Ni, respectively. The highest carbon gasification efficiency (CGE) and hydrogen gasification efficiency (HGE) of 23.61% and 23.55% were achieved with Ni/HY (Na 2 O, 0.8%). The gaseous produced mainly consisted of H 2 and CO 2 . The H 2 content in the gaseous products varied from 27.15 to 40.51% depending on the Ni/zeolites and increased with increasing the SiO 2 /Al 2 O 3 molar ratio of HZSM-5, which is 2.3–3.6 times higher than that of produced without catalyst. The H 2 yield varied between 2.57 and 3.61 mmol/g depending on the Ni/zeolites and increased from 2.19 to 5.61 mmol/g with increasing the SiO 2 /Al 2 O 3 molar ratio from 50:1 to 170:1, which is 3.6–7.8 times higher than that of produced without catalyst. Coke formation, surface area loss, and sintering of Ni could decrease the activity of the Ni/zeolites.
研究领域:
能源生物学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
WASTE MANAGEMENT
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2019
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IF 5.431
Chenyu Wang,Wei Zhu,Hao Zhang,Cheng Chen,Xihui Fan,Ying Su
The hydrothermal gasification of dewatered sewage sludge converts waste into syngas fuel (gas containing H 2 , CH 4 , CO, and CO 2 ), but the formation of char and tar by a side reaction restricts practical applications. In this study, the formation of char/tar by the hydrothermal gasification of dewatered sewage sludge at 300–400 °C for 5–90 min with a heating rate of 8–50 °C/min is investigated. The results showed that the formation of tar/char reached equilibrium after 30 min, and an increase in the temperature and heating rate reduced the char yield. However, a higher tar yield was achieved at the highest temperature. Experiments on sludge with different moisture contents were also conducted, and the formation of char/tar was inhibited at a higher moisture content. The addition of NaOH and H 2 O 2 can effectively reduce the char and tar yields, respectively. A lumped kinetic model for describing carbon conversion during the hydrothermal gasification of sewage sludge was developed to elucidate the char/tar formation mechanism. The experimental data were used to determine the model parameters, and the fitting results showed that solid–solid conversion from organic matter in sludge was the predominant char/tar formation pathway, with an activation energy of 7.1 kJ/mol. The experiments using the model compounds indicated that humus and protein are the main precursors of char and tar, respectively. This study provides insights for understanding the formation of char/tar from sewage sludge following hydrothermal gasification, which is vital for controlling the formation of char and tar to improve the gasification efficiency.
研究领域:
环境科学
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能源工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2025
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IF 4.3
Tianlong Liu,Peiyan Yang,Luyao Shen,Zhonghong Li,Yancheng Hu,Qi Li,Xiaobo Feng,Xiaoyan Zhao,Jingpei Cao
Alkaline oxidation is one of the methods for effective delignification of biomass and structural degradation of lignin. The depolymerized lignin has great potential to be valorized by hydrothermal gasification while little attempts have been made. The present authors subjected an alkaline lignin to oxygen oxidation in Na 2 CO 3 solution and investigated gasification performance of the lignin with a continuous flow reactor. The oxidative treatment decreased the molecular weight of lignin and produced large portions of acid-soluble fractions with a lower molecular weight. The depolymerized lignin was near-completely converted to H 2 , CH 4 and CO 2 at 340 °C with a Ru/C catalyst. The Ru/C catalyst maintained its activity for at least 480 min, with a negligible amount of coke deposition (1.0 %-C/h on average) and liquid effluent containing 55 − 150 ppm of organic carbon. The gasification efficiency of the depolymerized lignin achieved by Ru/C was superior to that of the raw lignin.
研究领域:
生物质能
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
·
IF 6.551
Mi Yan,Hongcai Su,Zhihao Zhou,Dwi Hantoko,Jianyong Liu,Jingyi Wang,Runpei Wang,Ekkachai Kanchanatip
The effluent of food waste (FWE) is generated during food waste treatment process. It contains high organic matter content and is difficult to be efficiently treated. In this study, the sample was collected from a 200 t/d food waste treatment center in Hangzhou, China. Subcritical and supercritical water gasification were employed to decompose and convert FWE into energy. The effects of reaction temperature (300–500 °C), residence time (20–70 min) and activated carbon loading (0.5–3.5 wt%) on syngas production and the remaining pollutants in liquid residue were investigated. It was found that higher reaction temperature and longer residence time favored gasification and pollutant decomposition, resulting in higher H 2 production and gasification efficiencies. It is noteworthy that the NH 3 -N was difficult to be converted and removed under current experimental conditions. The addition of activated carbon was found to increase the gasification efficiency. The highest total gas yield, H 2 yield, carbon conversion efficiency, gasification efficiency, total organic carbon removal efficiency and chemical oxygen demand removal efficiency were obtained from gasification at 500 °C for 70 min with 3.5 wt% activated carbon.
研究领域:
环境科学
·
能源工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2022
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IF 6.449
Yan-qing Song,Sonil Nanda,Wen-jie Cong,Jie Sun,Guo-hua Dong,Aneta Magdziarz,Zhen Fang,Ajay K. Dalai,Janusz A. Kozinski
Cotton stalk was gasified to produce H 2 with Ni-La based catalysts in subcritical and supercritical water. Approximately 90% H 2 yield was obtained under optimized conditions (360 °C, 0.5 g Ni-La catalyst loading, 0.5 g biomass and 10 min) by an orthogonal design with Ni-La/spent bleaching clay (SBC) materials. In addition, the H 2 yield of rice and wheat straw increased by 41.5 and 39.5 times, respectively at optimized conditions. It was found that the activity of Ni-La materials supported on SBC ash and Al 2 O 3 was similar, with H 2 yields of 108.3% and 115.1% at 380 °C, respectively in 5 min. SBC ash provided a high specific surface area (94.4 m 2 /g) for the Ni-La catalyst. La-promoted Ni/SBC (0.19 mmol/g) had a stronger acidity than Ni/SBC (0.16 mmol/g). Ni-La/SBC had a broad reduction peak, indicating the uniform dispersion of Ni on the support. Ni-La/SBC materials not only realized the reuse of SBC but also effectively promoted the hydrothermal gasification of agricultural wastes .
研究领域:
能源生物学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
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2020
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IF 3.744
Jie Sun,Lujiang Xu,Guo-hua Dong,Sonil Nanda,Hu Li,Zhen Fang,Janusz A. Kozinski,Ajay K. Dalai
Nickel-based catalysts with different supports and cobalt loadings were synthesized for hydrothermal gasification of cellulose at 350 °C. The activity of Ni catalysts was found in the order of Al 2 O 3 > spent bleaching clay ash > SiO 2 with H 2 yield of 80.6%, 69.0% and 57.0%. When 6 wt. % Co was added, 10Ni-6Co/Al 2 O 3 showed the highest H 2 yield of 88.4% i.e., 1.44 times that without Co addition. Catalysts were characterized by NH 3 -TPD, TPR, XRD, BET and XPS, showing that Ni-Co alloy formation promoted H 2 production. Single-factor experiments were conducted to study variables in the presence of 10Ni-6Co/Al 2 O 3 with the selected conditions of 0.5 g biomass and 20 min at 350 °C (achieving 94.9% H 2 yield from cellulose) for gasification of rice straw, peanut shell and cotton straw with the increase in H 2 yield by 51.4, 76.0 and 67.8 times. Ni-Co/Al 2 O 3 catalysts enhanced hydrothermal gasification of actual agricultural residues.
研究领域:
化学工程
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环境科学
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催化
·
可再生能源
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）