【作者】 张曦；

【导师】 程军； 刘建忠；

【作者基本信息】 浙江大学 ， 热能工程， 2018， 硕士

【摘要】 开发绿色可再生的生物航油替代传统石化航油能有效减少航空运输业二氧化碳排放,国内外许多航空公司开始试飞地沟油和棕榈油等制备的生物航油。但是大宗含油原料短缺是限制生物航油产业发展的关键瓶颈,微藻具有生长速率快和油脂含量高等优点故成为未来生物航油的理想原料。本文利用微藻生物柴油通过镍基梯度介孔分子筛双功能催化剂进行脱氧断键制航油范围烃类燃料,采用磺化处理增强催化剂酸性提高了藻基烃类燃料转化率和成分品质。将金属镍作为脱氧中心负载于分子筛时双功能催化剂出现强酸基(含量达0.41mmol/g)有效增强了酸性强度。负载后镍基梯度介孔Y分子筛的介孔孔径集中于10～20nm,10wt%金属镍颗粒负载于分子筛后结晶度完好。与未负载镍的催化剂相比,能有效催化藻油脱氧断键获得烷烃含量高和芳香烃含量低的航油范围烃类燃料。定向调控藻油脱氧断键反应提高了航油范围烃类产物中异构烷烃比例并使碳链分布更加均匀。优化调控脱氧断键反应温度和藻油流速等关键参数,在最佳反应温度275℃和藻油流速为0.02ml/min时得到藻油转化制航油范围烃类选择性由29.80%提高到58.18%,产物中烷烃的异构化比例由15.38%提高到46.40%,并适当提高了芳香烃含量达到11.45%,环烷烃和烯烃含量分别达到5.95%和1.54%,明显提升了航油范围烃类产物的成分品质。首次采用磺化处理增强镍基梯度介孔分子筛催化剂酸性提高了藻基烃类燃料转化率。磺化后分子筛出现了-SO3H磺酸基,使中强酸含量由0.31mmol/g提高到1.21mmol/g。随着磺化剂含量增加得到的磺化双功能催化剂,使微藻生物柴油制航油范围烃类燃料的转化率先增加后下降。当梯度介孔分子筛担载磺化剂达到最佳含量0.38ml/g时,微藻生物柴油制烃类燃料的转化率由82.13%提高到99.71%,烷烃选择性由31.21%提高到52.34%,环烷烃选择性由13.46%降低到0.57%,从而提高了藻基烃类燃料转化率并改善了成分组成。更多还原

【Abstract】 The development of green renewable bio-jet fuel alternative to traditional fossil jet fuel can effectively reduce the carbon dioxide emissions in the air transport industry.Many airlines both at home and abroad have started to test bio-jet fuel such as cooking oil and palm oil.However,the shortage of bulk oil-based raw materials is a key bottleneck that limits the development of the bio-jet fuel industry.Microalgae is an ideal raw material for bio-jet fuel with the advantages of fast growth rate and high oil content.In this paper,the microalgae biodiesel was catalyzed through hydrodeoxygenation and hydrocracking to produce hydrocarbon fuels within the jet fuel range over nickel-based gradient mesoporous zeolites as bifunctional catalysts and the sulfonation was used to enhance the catalyst acidity and increase algae-based hydrocarbon fuels conversion rate and compositional quality.The strong acidity(about 0.41mmol/g)appeared in the bifunctional catalysts when nickel was used as a deoxidation center on zeolites,which effectively enhanced the acid strength.The mesopore size of Ni-based gradient mesoporous Y zeolites after loading is concentrated between 10 to 20nm.The crystallinity of 10wt%metallic nickel particles loaded on zeolites is intact.Compared with the catalyst without nickel,the algae oil can be efficiently catalyzed through hydrodeoxygenation and hydrocracking to obtain the hydrocarbon fuels within the jet fuel range with high alkane content and low aromatic content.Directional control the hydrodeoxygenation and hydrocracking process of algae oil to increase the isoparaffin content in the hydrocarbon products within the jet fuel range and make the carbon chain distribution more uniform.Optimize the key parameters such as the reaction temperature and algae.oil flow rate,the selectivity of algae oil conversion to hydrocarbon within the jet fuel range was increased from 29.80%to 58.18%at the optimal reaction temperature of 275 ℃ and algae oil flow rate of 0.02ml/min,the isomerization ratio of paraffin in products increased from 15.38%to 46.40%,and the content of aromatics reached 11.45%and the content of naphthenes and olefins reached 5.95%and 1.54%respectively,which significantly improved the composition of hydrocarbon products within the jet fuel range quality.Sulfonation was used to enhance the acidity of nickel-based gradient mesoporous zeolites for the first time,which increased the conversion rate of microalgae biodiesel to hydrocarbon fuels.Sulfonated zeolites appeared-SO3H sulfonic acid group,the medium strong acid content increased from 0.31mmol/g to 1.21mmol/g.With the increase of sulfonation agent content,the conversion rate of microalgae biodiesel to hydrocarbon fuels within the jet fuel range over sulfonated bifunctional catalysts increased first and then decreased.When the sulfonation agent content loaded on the gradient mesoporous zeolites achieve the optimum content of 0.38ml/g,the conversion rate of microalgae biodiesel to hydrocarbon fuels increased from 82.13%to 99.71%,paraffin selectivity increased from 31.21%to 52.34%,aromatics selectivity decreased from 13.46%to 0.57%,thereby increasing algae-based hydrocarbon fuels conversion rate and improving the composition of hydrocarbon fuels within the jet fuel range.更多还原