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1.
Rosana Fatima Galindo Luis Antonio Barbosa Cortez Telma Teixeira Franco 《化学工程与技术》2020,43(8):1530-1537
An alternative for reducing emissions from marine fuel is to blend bio-oil from lignocellulose non-edible feedstocks to diesel fossil fuels. Phase diagrams of the ternary systems were built to represent the transition from heterogeneous regions to homogeneous regions. Four homogeneous blends of bio-oil of eucalyptus-bioethanol-marine gasoil were experimentally characterized with respect to the most important fuel parameters for marine engines: water content, flash point, low heating value, viscosity, and acidity. Blends with closer properties to marine gasoil replacement, lower costs, and environmental impacts should be tested for large engines. 相似文献
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在水热条件下通过无模板剂法合成了连续的ZSM-5沸石膜,并将其用于生物油的渗透汽化以进行高效脱水分离。ZSM-5沸石膜在强酸性、多组分的生物油体系中保持了很好的化学稳定性和优异的分离选择性,但在分离过程中面临着较强的膜污染问题,导致了膜通量的大幅下降。ZSM-5沸石膜的再生研究表明,膜的渗透通量随着再生温度的升高而逐渐提高。当再生温度为220℃时,ZSM-5沸石膜的渗透通量可以恢复至初始的88%。再生的机理研究表明,ZSM-5沸石膜中大量的晶内孔在生物油体系中极易被污染,从而导致渗透通量迅速下降;而相对较大的晶间孔却难以被完全堵塞,水分子在被污染的ZSM-5沸石膜中主要通过晶间孔进行渗透。上述结果表明,通过合理调控ZSM-5沸石膜的晶间孔的数量和尺寸大小可有效提升ZSM-5沸石膜在生物油中的渗透汽化脱水分离性能。 相似文献
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将经过不同温度煅烧的赤泥与玉米秸秆按照一定质量比混合,在500℃下进行催化热解实验,研究赤泥对玉米秸秆生物油组成的影响规律。经TG-DTG和XRD分析发现:600℃煅烧后赤泥(RM600)中含水矿物失水,1 000℃煅烧后赤泥(RM1000)中碳酸盐类化合物分解完全,并且发生了烧结反应。对生物油进行GC/MS分析发现:经过干燥的赤泥(RM)和600℃煅烧的赤泥对羧酸酮基化反应具有明显促进作用,酸类的量降低,酮类的量相应增加,同时对呋喃类的生成也有促进作用。其中,干燥赤泥降酸作用更明显,玉米秸秆与赤泥质量比1:5时,生物油中酸类的量由未添加赤泥时的23.85%降至0.90%。此外,2种赤泥对糖类和醛类都有抑制作用,而1 000℃煅烧的赤泥发生烧结反应,催化作用大幅降低,对生物油组分影响较小。 相似文献
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生物油气化对提高生物质能利用和保护环境具有重要意义。生物油气化选择乙酸、丙酮、丙三醇、苯酚、糠醛组成的混合物作为生物油模型物,在固定床圆柱形管式反应器进行气化模拟,用吉布斯自由能最小化法对其水蒸气催化重整制氢过程进行热力学分析。应用热动力学方程和质量平衡原理推算反应器模型,估算了反应热力学参数,通过Aspen Plus中的Gibbs反应器模拟生物油在不同温度下产物的平衡组成,计算出化学平衡体系的摩尔定压热容,利用Runge-Kutta法结合Matlab软件进行求解得出催化剂床层气化转化率;考察了反应温度对平衡时气体产物的影响。在固定床圆柱形管式反应器进行气化模拟实验,得出不同反应温度时反应产物气体产率和生物油气化反应较佳反应温度,通过比较得出实验结果与模拟计算值较一致。 相似文献
7.
生物油在受热条件下极易结焦,结焦是影响生物油规模化利用的重要因素之一,因此深入理解生物油受热结焦特性是实现生物油高效热转化利用的基础。本文从生物油热解过程的关键反应参数(温度、升温速率、气氛、压力、灰分)、生物油化学成分、生物油有机组分间交互作用、自由基反应特性等方面综述了生物油受热结焦特性相关研究进展,总结了反应参数对生物油热解结焦反应网络的影响,梳理了生物油各特征组分单独热解结焦及特征组分间交互作用对结焦特性的影响机制,并基于生物油结焦机理和焦炭的物化特性,总结了通过定向调控生物油结焦反应过程,将焦炭作为燃料和炭材料的潜在利用途径。最后,指出了明晰生物油受热结焦机理还需从生物油组分间交互作用机制和自由基反应机理的角度进一步探究。本文为实现生物油高效热转化利用提供了理论参考和借鉴。 相似文献
8.
Beatriz Valle Aingeru Remiro Naiara García-Gómez Ana G Gayubo Javier Bilbao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2019,94(3):670-689
Recent advances in lignocellulosic biomass valorization for producing fuels and commodities (olefins and BTX aromatics) are gathered in this paper, with a focus on the conversion of bio-oil (produced by fast pyrolysis of biomass). The main valorization routes are: (i) conditioning of bio-oil (by esterification, aldol condensation, ketonization, in situ cracking, and mild hydrodeoxygenation) for its use as a fuel or stable raw material for further catalytic processing; (ii) production of fuels by deep hydrodeoxygenation; (iii) ex situ catalytic cracking (in line) of the volatiles produced in biomass pyrolysis, aimed at the selective production of olefins and aromatics; (iv) cracking of raw bio-oil in units designed with specific objectives concerning selectivity; and (v) processing in fluidized bed catalytic cracking (FCC) units. This review deals with the technological evolution of these routes, in terms of catalysts, reaction conditions, reactors, and product yields. A study has been carried out on the current state-of-knowledge of the technological capacity, advantages and disadvantages of the different routes, as well as on the prospects for the implementation of each route within the scope of the Sustainable Refinery. © 2018 Society of Chemical Industry 相似文献
9.
不同催化剂催化裂化愈创木酚的性能 总被引:1,自引:0,他引:1
《石油化工》2015,44(4):459
以分子筛为活性组分、高岭土为载体制备HZSM-5/K,HZSM-5/MK,HY/K,5A/K 4种催化剂,采用FTIR技术对催化剂的表面酸性进行表征。以愈创木酚为模型化合物,在480~560℃、WHSV=3~6 h-1条件下的固定床反应器中考察4种催化剂的催化裂化性能。实验结果表明,催化剂表面酸量大小的顺序为:HY/KHZSM-5/K≈HZSM-5/MK5A/K;愈创木酚裂化过程中主要生成苯酚、甲基苯酚、乙基苯酚等单环芳烃和多环芳烃,在540℃、WHSV=4 h-1条件下单环芳烃产率较高,焦炭产率较低;HZSM-5/MK,HZSM-5/K,HY/K,5A/K 4种催化剂作用下得到的单环芳烃产率依次为57.14%,51.65%,36.74%,30.00%,焦炭产率大小的顺序为:5A/KHY/KHZSM-5/K≈HZSM-5/M K。 相似文献
10.
《International Journal of Hydrogen Energy》2014,39(35):19955-19969
Chemical looping hydrogen (CLH) process with renewable energy sources as fuel shows the potential of producing pure hydrogen with inherent capture of CO2 in a low-cost and sustainable way. The heavy fraction (HF) of bio-oil, derived from the fast pyrolysis of biomass and characterized as an energy carrier with difficulty in upgrading itself to bio-fuel or chemicals, was used in this study to generate H2. Four low-cost iron-based oxygen carriers including an ilmenite and three iron ores were initially evaluated with respect to their reducibility and the ability to minimize carbon or iron carbide (Fe3C) formation in a thermogravimetric analyzer (TGA). The reactivity and cyclic performance of the selected best candidate was then assessed in a laboratory scale fixed-bed reactor with HF bio-oil as fuel. The screening test in TGA showed that ilmenite was superior over the three iron ores in terms of promoting CO conversion and minimizing carbon or Fe3C formation. Ilmenite could maintain its increasing reducibility with the increase of surrounding CO concentration, in contrast with the iron ores that were deactivated seriously by the formed carbon or Fe3C. Subsequent CLH test with ilmenite and HF bio-oil showed that the reducibility and H2 production capacity of ilmenite were strongly dependent on the operating temperature. The steam oxidation step at 950 °C yielded H2 concentration and hydrogen yield exceeding all of those observed at the other investigated temperatures because of the deepest reduction degree of ilmenite at 950 °C. The decrease in the reducibility and H2 production capacity of ilmenite in the cyclic test could be ascribed to the poorer physical structure of ilmenite with cycles. 相似文献