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年产500吨生物质香兰素工程设计

时间:2021-08-16 20:31来源:毕业论文
以生物质原料4-甲基愈创木酚合成香兰素的工艺,主要研究了催化剂用量、反应温度和反应时间、溶剂种类几个因素对反应的影响

香兰素,又名香草醛,是一种广泛使用的带有浓郁奶香气味的食用香料,也是人类成功合成的第一种香料。人们可以从香荚兰干豆荚中可提取出天然香兰素,其含量大概占香荚兰干豆荚的2%~3%,但香荚兰种植成本太高,且此种方法收率低,无法满足市场需求。目前人们使用的香兰素主要是以石油资源为原料,通过化学法合成而获得。比较常见的方法有愈创木分法、木质素法、丁香酚法、黄樟素法等等。然而化学法合成工艺对环境造成严重污染,且其产物中同位素组成与天然香兰素有很大区别。特别是在食品添加剂领域中,天然香兰素的价格是合成香兰素的几百倍。而以生物质为原料通过氧化法制香兰素工艺成本低、收率高污染少,并且因其产物的同位素组成与天然香兰素十分接近,而受到高端市场的欢迎。70960

本文研究了以生物质原料4-甲基愈创木酚合成香兰素的工艺,主要研究了催化剂用量、反应温度和反应时间、溶剂种类几个因素对反应的影响。研究结果表明,不同溶剂、催化剂质量比、反应时间较佳操作条件如下:反应温度为83℃~86℃;以(CH3COO)2Co-4H2O为主催化剂,(CH3COO)2Ni-4H2O为助催化剂,m(4-甲基愈创木酚):m(催化剂)=1.0:0.01;反应时间为4小时,香兰素的转化率为99.58%,收率为75.1%。

本次设计依据小试结果,参考国内相关行业的工程实例和行业相关标准,设计工艺流程,其流程包括反应工段、甲醇回收工段、甲苯萃取工段、甲苯回收工段、香兰素精制工段。并且对所有工段进行了物料衡算,对其中的反应工段、甲醇回收工段、甲苯回收工段进行了热量衡算。对化工工艺流程中所使用的设备进行了设备选型,为了完成年产500吨生物质香兰素的工程设计,设定年工作天数为300天,每天出产1.7t香兰素。为了实现每天的出产目标,选择2个公称容积为6.3m3搪玻璃闭式搅拌容器进行连续反应。

本次设计依据工艺系统工程设计技术规定(HG/T 20570-1995)和化工装置设备布置设计规定(HG 20546-1992)等行业标准,参考《化工工艺手册》、《化学工程师技术全书》等工具书的设计要求进行设计。

项目成果:上海市科委地方高校能力建设项目《生物质香兰素绿色生产工艺关键技术研发》(80万)研究内容

毕业论文关键词: 香兰素;生物质;工程设计

R & D and design general description

Vanillin is a kind of material with a strong milk flavor, but also the first synthesis flavor by human successfully, its application areas are extensive. 2% to 3% natural vanillin can be extracted from vanilla pods, but the cost of vanilla is too high, and the yield of this method is low and can not meet the market demand. At present, people use vanillin is mainly based on oil resources as raw materials, obtained by chemical synthesis. However, the chemical synthesis process of the environment caused serious pollution, and its product isotopic composition and natural vanillin are very different. Especially in the field of food additives, natural vanillin prices are hundreds of times the synthesis of vanillin. And the cost of biomass as raw material through the oxidation process vanillin is low, the yield of high pollution less, and because of its product isotope composition and natural vanillin is very close, and it’s popular among the high-end market. 

In this paper, the process of synthesizing vanillin from 4 - methyl guaiacol with biomass feedstock was studied. The effects of catalyst dosage, reaction temperature and reaction time and solvent on the reaction were studied. The reaction conditions were as follows: the reaction temperature was 83 ℃ ~ 86 ℃; (CH3COO) 2Co-4H2O as the main catalyst, (CH3COO) 2Ni-4H2O as the co-catalyst, m (4-methyl guaiacol): m (catalyst) = 1.0: 0.01; the reaction time was 4 hours, the conversion rate of vanillin was 99.58% and the yield was 75.1%. And the material balance, heat balance, equipment selection and production line of 500 tons of biomass vanillin were designed for each section. 年产500吨生物质香兰素工程设计:http://www.youerw.com/huaxue/lunwen_80462.html

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