BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Xin Zhang,Ziguo Yuan,Qian Yao,Ying Zhang,Yao Fu
In this work, corn cob was used as raw material to selectively produce acetonitrile via catalytic fast pyrolysis (CFP) in ammonia over Ga/HZSM-5 catalyst. A series of catalysts with different catalyst carriers (including HZSM-5, USY, MCM-41, HY, and γ-Al 2 O 3 ) and active metals (including Fe, Co, Ni, Cu, Zn, Cr, Ca, Mg and Ga) were prepared and screened. The reaction conditions, such as temperature, ammonia flow rate and residence time were changed to investigate the effect on the product distribution and acetonitrile production. The results indicated that with the desired catalyst (2% Ga/HZSM-5) and optimal reaction conditions (Temperature 700 °C; ammonia flow rate 80 ml/min; residence time 2.4 s), the highest carbon yield of acetonitrile from corn cob with a value of 18.4% could be obtained, and the carbon selectivity in bio-oil was 83.5%. This study provides an economical and environmental-friendly method for the direct production of acetonitrile from abundant biomass.
研究领域:
能源与环境科学
·
生物质转化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2022
·
IF 3.656
Jiale Zhu,Siyan Yan,Guohao Xu,Xuedong Zhu,Fan Yang
A variety of HZSM-5 zeolites with different b-axis thicknesses and SiO 2 /Al 2 O 3 were fabricated by simply modifying urea content and Al source feeding in the initial gel, respectively. Multiple characterization technologies including XRD , SEM, N 2 adsorption-desorption, NH 3 -TPD and Py-IR were employed to investigate physicochemical properties of these samples and the possible crystallization mechanism was proposed that adsorption of urea molecules on (010) facet was the key factor for fabricating thin-sheet HZSM-5 zeolites. The results of hexane cracking reaction revealed that the selectivities of light olefins reached 46.5% when controlling b-axis thickness to 340 nm, exceeding the control sample by 12.2%. Furthermore, the effect of SiO 2 /Al 2 O 3 under this b-axis thickness was also investigated and concluded that keeping SiO 2 /Al 2 O 3 to 200 could exhibit the optimum catalytic performance with the conversion of 95.5% and light olefins selectivities of 56.7%. The reaction conditions were optimized to be 600 °C at the N 2 flow rate of 25 mL/min and WHSV of 3 h −1 to arouse the best performance. Under this condition, the distribution of ethene and propene was quite close to that of thermodynamic equilibrium. Based on these results, the primary and secondary products were uncovered, and further the reaction pathway of hexane cracking was disclosed. This new strategy to synthesize sheet-like catalysts for enhancing the catalytic properties in hexane cracking also laid a solid foundation for the study of the catalysts on light oil cracking in industry.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2018
·
IF 3.956
Shiyou Xing,Pengmei Lv,Che Zhao,Ming Li,Lingmei Yang,Zhongming Wang,Yong Chen,Shijun Liu
Non-H 2 and solvent-free catalytic conversion of waste lipids to liquid hydrocarbons is of great interest because of the associated low-cost, full-safety, and easy-operability. In this work, a solvent-free catalytic process for deoxygenating oleic acid was performed in H 2 and non-H 2 (N 2 , CH 4 , and CO 2 ) media over nano-Ni/HZSM-5. 8-Heptadecene, a primary product obtained at 320 °C in four media, was derived from the straightforward decarboxylation of oleic acid. In non-H 2 medium at 360 °C, the formation of C 8 –C 15 alkanes was enhanced, with yields of ca. 65.05 mol%, 70.71 mol%, and 73.09 mol% for N 2 , CH 4 , and CO 2 , respectively. A low yield of 49.67 mol% C 8 –C 15 alkanes in H 2 medium suggested that the H 2 medium reduced catalytic cracking . This was due to the preferential formation of stable heptadecane from 8-heptadecene in the presence of abundant H 2 . The absence of H 2 favored the cracking of 8-heptadecene. These cracked products were further converted to C 8 –C 15 alkanes, for which a mass supply of hydrogen was mandatory. Gas-phase reactions including methanation , Fisher-Tropsch (F-T) synthesis, and water-gas shift (WGS) reactions between deoxygenated gas products and reaction media provided significant pathways for the hydrogen required for the formation of alkanes. The CH 4 medium also acted as a hydrogen source due to its decomposition, catalyzed by nano-Ni/HZSM-5. Coke was substantially formed in all the four media. It was highlighted that the medium of H 2 favored the formation of aliphatic cokes, whereas the non-H 2 media, particularly the CO 2 medium, facilitated aromatic coke species on account of its weak oxidizability. Additionally, there was a severe loss of loaded Ni nanoparticles under H 2 medium but a slight Ni loss in CO 2 medium, which was proposed to the reason of aromatic cokes formation at the catalyst surface , acting as a trap for the loaded Ni nanoparticles.
研究领域:
化学工程
·
能源科学
✓ 已验证
DOI
高影响因子
CHEMISTRY & BIODIVERSITY
·
2024
·Vol. 21
·期 6
·e202400150
·
IF 2.3
Long Ren,Yupu Xu,Wenjun Chen,Changsen Zhang
Experiments were conducted in this study on the co-hydropyrolysis of three components of biomass (cellulose, hemicellulose, and lignin) and HDPE by using SR-Pd/Trap-HZ-5 as catalyst. To control the variable, we use the same experiment conditions in co-hydropyrolysis: Si/Al ratio of 50, Pd load 1 %, catalyst to reactant ratio of 1 : 10, 1 MPa, 400 °C, reaction time 1 h. Use XRD, TEM, BET, and NH 3 -TPD to confirm catalyst successful synthesis; use pine sawdust (PW) co-hydropyrolysis with HDPE to analyse catalytic activity; and use GC/MS to characterize the chemical composition of the bio-oil from the co-hydropyrolysis of biomass components and HDPE. The results show that cellulose has a significant synergistic effect with aromatic hydrocarbon production, whose selectivity was 93.3 %; hemicellulose has a synergistic effect; aromatic selectivity can reach 75.1 %; and a negative synergistic effect between lignin and HDPE was shown as the selectivity of aromatic hydrocarbons decreased from 62.1 % to 15.6 %. Graphical
研究领域:
能源与燃料化学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2020
·Vol. 96
·期 1
·256-263
·
IF 2.008
Guo Lulu,Wang Zhichang,Wang Jianfeng,Wang Zheng,Xue Shaozong,Jiang Xinge,Lu Tianliang,Xu Jun,Zhan Yuzhong,Han Li
c -Axis-oriented HZSM-5 zeolites were directly synthesized by introducing crosslinked polyacrylamide (C-PAM) hydrogels into ZSM-5 synthesis gels. The growth orientation of the crystals as well as the acidity of ZSM-5 could be modulated by the C-PAM content in the synthesis gel. The crystal growth along the a -axis and b -axis was obviously restricted, whereas c -axis growth was distinctly promoted with increasing C-PAM content, which was probably due to the C-PAM having stronger interactions with the {010} and {100} facets than the {101} facet. Sample Z-2, which was prepared with 2% C-PAM exhibited the shortest b -axis length elongated prism structure and strong acid sites. Furthermore, Z-2 exhibited excellent catalytic performance in the methanol-to-olefin (MTO) reaction showing the highest methanol conversion (100%) and the light olefin selectivity (TOS) (81.2%), as well as the longest lifetime (>23 h).
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Guozhang Chang,Shanshan Dai,Huifen Kang,Jie Li,Yong Liu,Jian Zhang,Qingjie Guo
Limited knowledge regarding the controlled preparation of aromatic hydrocarbons (AHs) via catalytic pyrolysis of individual organic components hinders high yields of lignocellulosic biomass-based AHs. This report describes a systematic investigation of AHs generation following catalytic pyrolysis of organic components referring to cellulose, xylan, and lignin. Results show that in a programmed-heating process (20 °C/min), a (Ca-Fe)/HZSM-5 catalyst promoted the degradation of cellulose, xylan, and lignin with respective increment ratios of 24.56 %, 17.29 % and 19.45 %, and significantly increased the release of benzene during the pyrolysis of cellulose and xylan. In a fast-heating process (20 °C/ms), Ca-Fe alone presented a positive effect on bio-oil yield from cellulose, whereas HZSM-5 and (Ca-Fe)/HZSM-5 afforded high bio-oil yields from all three components. Notably, Ca-Fe and HZSM-5 exhibited synergistic effects on the bio-oil and AHs yields following cellulose pyrolysis, and on AHs yield following xylan pyrolysis. Alcohols, aldehydes, and furans were suitable precursors for generating AHs via pyrolysis of both cellulose and xylan. Lignin conversion to AHs involved various potential reaction pathways, including dehydration-deoxygenation-aromatization and dehydration-hydrodeoxygenation. The orders of (Ca-Fe)/HZSM-5 catalyzed pyrolysis of individual components towards AHs generation were xylan > cellulose > lignin. The presence of Ca-Fe particles inhibited deactivation of HZSM-5 in pyrolysis of a cellulose/xylan/lignin mixture.
研究领域:
能源植物学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Lele Jin,Wenzhi Li,Qiying Liu,Longlong Ma,Song Li,Yang Liu,Baikai Zhang,Qi Zhang
The liquid fuel (made of C 5 /C 6 alkanes) was obtained directly from the hydrogenolysis of microcrystalline cellulose (MCC) with Ir-VO x /SiO 2 combined with HZSM-5 as the composite catalyst in a biphasic system (n-dodecane + H 2 O). The performance of the catalyst was investigated by carrying out a series of experiments using various V/Ir molar ratios , catalyst dosages, reaction temperatures, reaction time, hydrogen pressure and substrates. At the optimized conditions, the cellulose was almost completely converted, and at the same time, a high C 5 /C 6 yield of 85.1% was obtained at 210 °C for 24 h and 6 MPa with the V/Ir molar ratio being 0.13. These results not only proved that Ir-VO x /SiO 2 (V/Ir = 0.13) has excellent performance for the hydrogenolysis of MCC to liquid alkanes, but also indicated that vanadium is a good metal promoter for iridium . In addition, it was proven the C5/C6 alkanes were obtained via sorbitol through the combined effect of Ir-VO x /SiO 2 and HZSM-5.
研究领域:
催化化学
·
可再生资源转化
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2022
·
IF 6.449
Shaoqing Wang,Zhihe Li,Weiming Yi,Peng Fu,Xueyuan Bai
Catalytic pyrolysis of corn cob lignin were preformed using a tailored HZSM-5 @Al-SBA-15 hierarchical zeolite for the production of value-added aromatic hydrocarbon. Resulted showed that the highly ordered two-dimensional p6mm mesoporous shell could uniformly form on the surface of HZSM-5 core phase. The porosity and acidity of the HZSM-5 @Al-SBA-15 could be tailored by adjusting the TEOS/HZSM-5 mass ratio in the synthesis process. The aromatic hydrocarbon components regulated due to pre-cracking and enhanced diffusion via the mesoporous shell, as well as the retained shape-selectivity of the HZSM-5 core. Herein, the relative content of MAHs reached 45.02% with fewer poly-aromatic hydrocarbons (PAHs) of 25.91% when the TEOS/HZSM-5 mass ratio of 1.0. However, the length of the diffusion path had a certain impact on the anti-coking behavior. The catalytic stability of the hierarchical zeolites was also improved, with less coke formation than HZSM-5 alone. This work demonstrates that using a tailored hierarchical zeolite to regulate aromatic hydrocarbon components is feasible, and provide a reference for the practical application of agricultural crop wastes.
研究领域:
能源与环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2024
·
IF 4.6
Junfu Zhou,Yuting Miao,Hongxin Ding,Yuanhang Ren,Lin Ye,Bin Yue,Heyong He
Direct and stable conversion of CO 2 to aromatics (CTA) is an attractive route for reducing CO 2 emissions. However, due to the chemical inertness of CO 2 , direct CTA reaction with high aromatics selectivity is still challenging. In this work, a tandem catalyst Zn 0.1 Ti 0.9 O x /HZSM-5 with appropriate density and strength of acid sites exhibits a high aromatics selectivity of 67.2% and long-term stability over 100 h. Furthermore, the total selectivity of benzene, toluene, and xylene achieves 24.1% over Zn 0.1 Ti 0.9 O x /HZSM-5 with a modified hydrophilic surface. In addition, the CTA via the formate route has been determined in this reaction system.
研究领域:
催化化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RENEWABLE ENERGY
·
2024
·
IF 9
Hong Tian,Rui Zhu,Guangming Zhu,Jiawei Wang,Yi Cheng
The limitation in bio-oil quality hampers its further utilization in the fuel or chemical industry. This study employed a combination of tetra propylammonium hydroxide (TPAOH) and NaOH solutions for HZSM-5 desilication to enhance the yield of monocyclic aromatic hydrocarbons in the catalytic co-pyrolysis of wheat straw with polyethylene. Results revealed hierarchical HZSM-5, prepared with equal mole concentrations of NaOH and TPAOH, exhibited optimal catalytic performance. The bio-oil from this process had an aromatic content of 72 %, with monocyclic aromatic hydrocarbons (MAHs) constituting 56.26 %. Further optimization was achieved through iron modification of hierarchical HZSM-5. The addition of 0.5 % iron-modified hierarchical HZSM-5 increased the aromatic hydrocarbons to 80.57 %, with BTX compounds (benzene, toluene, and xylene) reaching a selectivity of 61.9 %. This approach reduced polycyclic aromatic hydrocarbons (PAHs), contributing to less coke formation, presenting a promising method for high-quality bio-oil.
研究领域:
能源化学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Jiayu Feng,Fei Wang,Chi Wang,Kai Li,Ping Ning,Xin Sun,Lijuan Jia
A series Ce m Cu n O x /HZSM-5 sorbents were introduced to remove PH 3 in low-temperature and low-oxygen environments. The effects of copper loading and cerium doping on the adsorption–oxidation performance of the sorbents were investigated. Experimental results showed that doping with 1 wt% of cerium (Ce 1 Cu 30 O X /HZSM-5) could significantly improve the performance of the sorbent. The PH 3 breakthrough capacity was identified as 114.36 mg(PH 3 )•g sorbent -1 . In addition, after three thermal regeneration cycles, the sorbent still has ideal performance. X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS) analyses exhibited that CuO was the main active species, and Ce-doping can increase the chemisorption oxygen on the surface of the sorbent. BET results demonstrated that the introduction of cerium could improve the specific surface area and pore volume of sorbent. Hydrogen temperature-programmed reduction (H 2 -TPR) and scanning electron microscope (SEM-EDS) indicated that cerium species played an important role in uniformly dispersing copper species on the HZSM-5 surface and improving the oxidation performance of sorbent. Moreover, the reaction products and mechanisms were also investigated by XRD, XPS, and in-situ FTIR spectra. The results indicated that the consumption of CuO and the accumulation of phosphorus species (e.g., P, P 2 O 5 , and Cu 3 P) on the surface and inner pores of the sorbent were the primary reasons for the deactivation of the sorbent.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Wenhui Li,Jiaxing Zhang,Xiao Jiang,Minchen Mu,Anfeng Zhang,Chunshan Song,Xinwen Guo
Carbon dioxide (CO2) hydrogenation to gasoline through the methanol-mediate route using the metal oxide/ZSM-5 tandem catalyst has attracted considerable attention to reduce the pernicious effect of CO2 on global climate change and to reduce our dependence on fossil fuels. The C5+ molecules are preferred to pass through the straight channels of ZSM-5 zeolite, where side reactions may occur on the acid sites and the catalyst is deactivated due to pore blockage. Thus, the thickness of ZSM-5 along the straight channel, namely the b-axis direction, is crucial to manipulating the product distribution and catalyst lifetime. Here, HZSM-5 nanosheets with different thicknesses (2 nm to 2 μm) along the b-axis were synthesized controllably and composited with In2O3/ZrO2 as tandem catalysts for CO2 hydrogenation to gasoline. In2O3–ZrO2/HZSM-5 with a thickness of 20 nm shows the highest selectivity toward C5+ hydrocarbons under isoconversional conditions and no deactivation after 150 h of reaction with less carbon deposition compared with the 2 μm one. Comparative activity tests and characterization results demonstrate that an appropriate length of straight channels can benefit the production of C5+ hydrocarbons through the polymerization of short-chain molecules while preventing the cracking of long-chain hydrocarbons on acid sites. Adding an appropriate loading of Co into tandem catalysts with optimal composition gives rise to further enhancement in CO2 conversion by 10%, and a slight increase in C5+ selectivity. This can be attributed to the Co-induced hydrogen spillover from metallic Co to support ZrO2, facilitating the formation of the key intermediate and its subsequent hydrogenation steps. This study provides insights into designing effective and anti-carbon deposition tandem catalysts for CO2-to-gasoline by manipulating the channel length–resident time–acidity relationship and the promoter effect.
研究领域:
化学工程
·
催化材料科学
✓ 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）