JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2023
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IF 6
Tao Shen,Qingya Liu,Zhenyu Liu
Balancing the rates of coal radical fragments’ generation and hydrogen donation is crucial to inhibit the radical fragments’ condensation for a high oil yield and low hydrogen consumption in direct coal liquefaction (DCL). Two-stage liquefaction (TSL) has been proposed to be effective for balancing these rates under mild conditions but little work can be found in the literature on the comparison of TSL with single-stage liquefaction (SSL). This work studies direct liquefaction of two low-rank coals (NMH and SW) of very different volatile content under various TSL and SSL schemes in systems with different hydrogen donation ability. The coal conversion and products yield in different liquefaction schemes are correlated with their organic structure characterized by 13 C NMR and predicted by a structure model. It is found that for the total 40 min liquefaction, the TSL scheme with 10 min at 420 ℃ followed by 30 min at 455 ℃ results in the highest liquid yield and lowest hydrogen consumption per liquid yield when the coal is very active but the hydrogen donation ability is insufficient. Otherwise, SSL at 455 ℃ is preferred. The coal conversion, liquid yield and hydrogen consumption per liquid yield of NMH under above TSL scheme at coal:THN= 1:2 are 85.5 wt%, 55.9% and 48.4 mmol-H/g-Liquid, respectively.
研究领域:
能源化学
·
煤炭加工
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2016
·
IF 4.917
Leichang Cao,Cheng Zhang,Shilai Hao,Gang Luo,Shicheng Zhang,Jianmin Chen
This study examined the effect of glycerol used as a co-solvent on yields of bio-oil derived from rice straw through hydrothermal liquefaction (HTL). The reaction was conducted in a high-pressure batch reactor with different volume ratios of glycerol to water. The quality of the derived bio-oil was analyzed in terms of its elemental composition, heating value, water content, ash content, and acid number. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry were conducted to analyze the chemical composition of the derived bio-oils. The following optimal conditions were obtained: 1:1 vol ratio of glycerol to water with 5 wt% of Na 2 CO 3 at 260 °C for 1 h. Under these conditions, 50.31 wt% of bio-oil and 26.65 wt% of solid residue were produced. Therefore, glycerol can be used as a co-solvent in HTL of rice straw at moderate temperatures to obtain bio-oil with high yield and quality.
研究领域:
能源植物学
·
可再生能源工程
✓ 已验证
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Hao Wu,Xiaoxiao Li,Hangyan Ji,Birte Svensson,Yuxiang Bai
High substrate viscosity during the production process suppressed the formation of gamma-cyclodextrin (γ-CD) from starch . Although liquefaction can be carried out by enzymes with high temperature optimum, some CGTases of interest are not suitable due to loss of activity at the gelatinization temperature. In order to apply a gamma-cyclodextrin glucosyltransferase (γ-CGTase) with an optimum temperature of 50 °C to the liquefaction of 10% w/v cassava starch, an improved process combining moderate heat treatment (30 °C increased to 70 °C) with enzymatic treatment was established. The substrate viscosity dropped from 2456 to 23 cP after the pretreatment, and the rate of γ-CD production increased from 10.43 to 26.34%. This process was further applied to the liquefaction of 30% w/v cassava starch, and the pretreated substrate was finally converted into 21.81% γ-CD. In general, evaluation indicators and basic principles of starch pretreatment were established, providing a reference for the production of γ-CD.
研究领域:
生物化学
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食品科学
✓ 已验证
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 8
·926
·
IF 4.501
Chunling Wu,Linge Ma,Yufei Zhu,Xuqiang Guo,Yongli Wu,Zhen Wu,Xian Zhang,Lihua Hou
In this paper, the extraction residue of direct coal liquefaction residue-DCLR(ER)was used as raw material. The high-temperature reaction mechanism of Mo compound in DCLR(ER)was investigated using a synchronous thermal analyzer and the Factsage database. The high temperature reaction of DCLR(ER)-MoO3in an oxygen atmosphere consists of pyrolysis of organic components at 400–600 °C, molybdenum trioxide sublimation at 747–1200 °C, and a stable stage at 600–747 °C. The thermal reaction process of the DCLR(ER)-MoS2system in the oxygen atmosphere involves the pyrolysis of unreacted coal and asphaltene, the oxidation of molybdenum sulfide at 349–606/666 °C, the diffusion of MoO3at 606/666–85 °C, and the sublimation reaction process of MoO3at 854–1200 °C. The results show that the lower heating rate can promote the oxidation of the Mo compound and the sublimation of molybdenum trioxide. On the other hand, the oxides of aluminum, calcium, and iron in DCLR(ER)can inhibit the oxidative pyrolysis efficiency of the DCLR(ER)-MoS2system.Keywords:direct coal liquefaction residue;molybdenum;high temperature;reaction mechanism
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Algal Research-Biomass Biofuels and Bioproducts
·
2024
·
IF 4.6
Luqiu Lin,Jianhui Zeng,Chuxuan Zhang,Zhengkang Peng,Xun Gong
This study reports the transformation of three typical heavy metals (As(III), Hg(II), and Pb(II)) during the process for magnetic harvesting and subsequent liquefaction in ethanol of microalgae. The magnetic harvesting process of Chlorella Vulgaris (CV) was simulated using a co-precipitation method, achieving the highest magnetic harvesting ratio of 98.95 % at a pH of 8 and an iron-algae ratio of 0.4 g/g. Then the magnetically harvested CV was subjected to liquefaction in ethanol to explore the speciation and migration of As(III), Hg(II), and Pb(II). The environmental risk assessment of above three heavy metals in the bio-oil and biochar was assessed according to the Risk Assessment Code (RAC). Hg(II) and Pb(II) were found to be effectively stabilized and immobilized in the biochar, while As(III) exhibited a propensity to migrate into the bio-oil and existed mostly in the dangerous speciation such as fraction associated with Fe and Mn oxides and fraction bound to organic matter. It reflects a high environmental risk and necessitates a pre-removal treatment.
研究领域:
环境科学
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2024
·
IF 9
Tao Lu,Zhiwen Ma,Yali Pan,Zhenyu Wu,Yupeng Yuan,Yingqiang Sun
Hydrothermal liquefaction (HTL) of microalgae for bio-oil production is a promising strategy to avoid extensive fossil fuel utilization, while tandem amidation and Maillard reactions during hydrolysis of cellular compounds unavoidably result in formation of nitrogen containing (N-containing) compounds, reducing quality of bio-oil. Accordingly, VO 4 3− intercalated Cu–Fe layered double oxides named as Cu 2 Fe-VO 4 -LDO is firstly synthesized to both catalyze hydrolysis of cellular compounds and block N-containing compounds formation. The results indicate Cu 2 Fe-VO 4 -LDO can improve bio-oil yield from 19.32 to 20.32 wt%, with decrease of N/C ratio from 0.70 of control to 0.67 of experimental group, and increase of H/C ratio from 0.129 to 0.132. The insert of VO 4 3− provides more strong-acid sites, which are beneficial to hydrolysis of cellular compounds. Meanwhile, more strong-base sites of Cu 2 Fe-VO 4 -LDO promote decarboxylation of fatty acids and removing amino-group of amino acids, subsequently improve production of alkanes. Furthermore, the reversible oxidation of VO 4 3− promotes oxidation of reducing sugars, blocking tandem amidation and Maillard reaction between intermedia of hydrolyzed lipids, carbohydrates, and proteins. This work reports a methodology for synthesis of Cu 2 Fe-VO 4 -LDO with strong acid-base sites and reversible oxidize interlayer sites, providing a strategy to simultaneously improve bio-oil yield and reduce its N/C ratio.
研究领域:
能源生物学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2020
·
IF 7.539
Haiwei Jiang,Liangliang Fan,Chang Cai,Ying Hu,Fenghua Zhao,Roger Ruan,Weiran Yang
The hydrothermal liquefaction (HTL) of As enriched Pteris vittata L. (PVL, hyper-accumulator biomass) was performed with the recycled aqueous phase as reaction medium, aiming to dispose the biomass with high water content and produce high-quality bio-oil. After three times of aqueous phase recycling at 275 °C, 30 min, the bio-oil yield increased to 30.32% from 21.54% and the higher heating value (HHV, 28.51 MJ/kg) of the bio-oil was higher than that of the bio-oil from HTL with pure water (26.80 MJ/kg). The main compounds detected in bio-oils were phenols, ketones, hydrocarbons, and aldehydes. Acetic acid (17.21–24.77 mg/mL) was dominant in the aqueous phases, resulting in the low pH (4.31–4.89). The heavy metals (Cu, Pb, Zn, Cd) mainly remained in bio-char whereas As was transferred to aqueous phase. Thus, HTL by aqueous phase recycling could be a promising way for PVL treatment to obtain high-quality bio-oil and arsenic recovery.
研究领域:
环境科学
·
能源植物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Carbon Resources Conversion
·
2018
·
IF 0
Yu Chen,Kejing Wu,Qisong Lin,Yulong Wu,Yin Tang,Mingde Yang
Hydrothermal liquefaction (HTL) is one of the most promising technologies for conversion of microalgae, and catalysts with high hydrothermal stability are required for controllable HTL. In this article, SBA-15 incorporated with transition metals (Ni, Pd, Co and Ru) were synthetized via double-template method for catalytic HTL of microalgae. The results showed that metal incorporated SBA-15 represented high hydrothermal stability at 613 K. The incorporated Ni, Co and Ru was dispersed in SBA-15 enhancing the hydrothermal stability. The catalysts greatly influenced the chemical composition of the obtained bio-oil, which contained a higher percentage of furfural derivatives and a lower content of fatty acids and N-containing compounds, thus bio-oil quality was improved significantly. Higher hydrothermal stability and specific surface areas of Co-SBA-15 contribute to the highest preformation with 78.78% conversion and 24.11 wt% bio-oil yield. Metal incorporated SBA-15 provides a potential application for biomass conversion in high-temperature aqueous phase.
研究领域:
生物能源
·
催化化学
✓ 已验证
产品关联
DOI
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Jian Wei,Yucui Hou,Tianqi Huang,Aohua Zheng,Shuhang Ren,Weize Wu
Identifying the source of products in lignin hydro-liquefaction oil is crucial for assessing the lignin conversion efficiency. The utilization of hydrogen donor solvents (HDSs) complicates the determination of whether polycyclic aromatic hydrocarbons (PAHs) derive from lignin or HDS. Thus, identifying the source of PAHs in the oil can improve our understanding of lignin structures and enhance its utilization. To address this challenge, 1,2,3,4-tetrahydroquinoline (THQ) was used as an HDS to trace products within the oil. The results showed that (1) lignin could be completely liquefied in THQ under optimal conditions: a THQ/lignin mass ratio of 0.5, a reaction temperature of 450 °C, an initial H2 pressure of 8 MPa, a reaction time of 4 h, and a molybdenum sulfide/lignin mass ratio of 1; (2) PAHs with 2–6 rings were identified in the oil and confirmed to derive solely from lignin through qualitative and quantitative analyses via GC–MS rather than THQ.
研究领域:
能源化学
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环境科学
·
生物质转化
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2022
·
IF 8.129
Chuxuan Zhang,Jianhui Zeng,Luqiu Lin,Yang Peng,Xiaomin Li,Xun Gong
As the representative of the 3rd generation feedstock of biodiesel , microalgae show extraordinary advantages for energy demands. Magnetic separation is a proven and effective method for microalgae harvesting. This study aims to investigate the effect of unrecovered magnetite-based nanoparticles (Fe 3 O 4 NPs) after microalgae harvesting on the bio-oil quality, especially nitrogen content in the subsequent production. Co-liquefaction of Chlorella Vulgaris mixed with three residual amounts (1 wt%, 5 wt%, and 10 wt% of microalgae addition) Fe 3 O 4 NPs in ethanol at 220 and 260 °C were performed. Ethanol can provide hydrogen in situ during liquefaction , and the catalytic activity of Fe 3 O 4 to hydrogenation reaction enhances the yield and quality of bio-oil. At 260 °C and 5 wt% NPs dosage, the bio-oil yield can reach up to 79.71%. The addition of NPs reduces the relative N content of bio-oil by more than 16.90%. GC/MS analysis shows that the nitrogen heterocyclic compounds are significantly reduced about 60%; instead, hydrocarbons are increased in the bio-oil. It implies that Fe 3 O 4 NPs are beneficial to the denitrogenation of bio-oil during microalgae liquefaction in ethanol.
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
RENEWABLE ENERGY
·
2017
·
IF 4.357
Rafia Younas,Shilai Hao,Liwu Zhang,Shicheng Zhang
In this study, rice straw as an abundant agricultural waste was subjected to hydrothermal liquefaction for production of bio oil . The series of batch experiments were conducted at different temperatures (200 °C, 230 °C, 260 °C, 280 °C and 300 °C) for reaction time of 120 min with and without NiO nanocatalyst. The resulting bio-oil was categorized into light and heavy oils (LO and HO). In presence of nanocatalyst, the yields of LO and HO were maximized up to 13.2% and 17.2% at 300 °C, respectively. The carbon recovery of bio oil was significantly improved to 52.8% with 46.6% energy recovery in catalyzed reaction. Typical H/C and O/C atomic ratio of catalyzed HO are 1.2 and 0.3 respectively. The highest calorific values of LO and HO are 24.9 MJkg −1 and 31.9 MJkg −1 respectively. The tested nanocatalyst increased the yield of bio oil, but could not incite the elemental compositions and heating values of bio oil. The valuable chemical compounds in bio-oil had been analyzed by GC-MS. The LO samples mainly contained phenols, alcohols and ketones while HO consisted alkanes and organic acids. Additionally, aldehydes and other organic compounds were also found in products.
研究领域:
能源科学
·
环境科学
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2021
·
IF 7.033
He Li,Shisheng Liang,Yucui Hou,Yupeng Wang,Shuhang Ren,Weize Wu
Direct coal liquefaction (DCL) is not only for fuel but also for chemicals, which shows high efficiencies in atom utilization and energy. The study on coal structure is important to select coal for direct liquefaction . Naomaohu coal is a kind of subbituminous coal and a typical coal for direct liquefaction . In this work, the structure of Naomaohu coal was investigated via alkali‑oxygen oxidation , ruthenium ion catalyzed oxidation and physical analyses and a representative structural model with a model size of 128,755 amu was constructed. The structural characteristics show that the ratio of single-, double-, triple-, and quadruple-aromatic rings is 149:164:102:63. The triple- and quadruple-rings aromatic structures are mainly connected by C C bonds of 2–4 carbon atoms. The single- or double-ring is connected on the triple- and quadruple-rings aromatic structures through ether or ester bonds , which can be broken easily under mild conditions. Long alkyl side chains with carbon atoms from 13 to 25 accounting for 0.91 wt%. The high H/C, high oxygen content (mainly weak bonds such as ether and ester bonds between aromatic clusters), abundant single-, double-, triple, and quadruple-aromatic rings, and alkyl bridge bonds of 2–4 carbon atoms are beneficial to the mild liquefaction of Naomaohu coal
研究领域:
化学工程
·
能源科学
✓ 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）