在超声波辅助下的生物催化原油脱硫的作用机制研究

项目名称： 在超声波辅助下的生物催化原油脱硫的作用机制研究

项目编号： No.21507052

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 化学工业

项目作者： 唐琼

作者单位： 乐山师范学院

项目金额： 21万元

中文摘要： 随着石油开采期的延长，石油资源的日益枯竭，市场上供应的原油趋向于重质化，含硫化(2%以上)，含硫石油产品燃烧所产生的SOx是引起酸雨、PM2.5等一系列环境问题的主要污染污染物之一。传统的加氢脱硫方法需要在高温、高压下加催化剂进行，条件苛刻，运行费用高；且难以脱除多环芳香杂环化合物中的硫。生物催化脱硫因其低耗能，低投资，低污染等优点在燃料油脱硫领域迅速发展，但还存在效率低，耗时长等缺点。本研究旨在采用超声波对原油进行空化预处理，改善原油的理化性质，提高处理过程中油/水混合比例，使油中的含硫化合物转化为更易被细菌氧化的物质，提高原油生物脱硫的效率，缩短脱硫周期；重点探讨超声波对油中含硫化物的作用机制与能力；研究脱硫菌对超声波处理油中硫化物的脱除规律及氧化机制；探讨超声波与生物联合脱硫的耦合机制与最优工艺条件，为原油脱硫提供新的理论和方法。

中文关键词： 原油；生物催化脱硫；超声波援助；作用机理

英文摘要： Recently the petroleum industries are facing tremendous challenges due to increasing demand for gasoline and diesel fuels with stringent environmental regulations. The gradual decline of the conventional petroleum fuel has forced the refiners to process heavy crude. Heavy crude oil contains elevated levels of sulfur (1.5-4 wt%) which generate serious air pollution during combustion due to SOx emission. Therefore, there is an urgent need for removing the main contaminants such as sulfur from crude oil. .Currently, oil sulfur content is treated and removed by hydrodesulfurization (HDS) process for industrial purpose, in which hydrogen gas is used in presence of metallic catalysts (metal oxides) to reduce sulfur to H2S. However, to reach a satisfactory level of sulfur removal, this process requires high temperature (200-450°C) and high pressure (up to 100atm). Moreover, it is difficult to remove some hetercyclic sulfur compounds such as dibenzothiophene (DBT) and substituted DBTs which are major sulfur content in heavy crude oil. .Biodesulfurization (BDS) process using microorganisms is known to be an alternative technology to remove sulfur from crude oil with mild processing conditions and reasonably low treatment cost. Moreover, BDS processes have been expected to remove the recalcitrant organic sulfur compounds found after the conventional hydrodesulfurization (HDS) treatment. For the BDS process to be effective, however, the solubilization of insoluble or slightly soluble organ sulfur compounds into aqueous solution is a prerequisite. It is well known that the use of ultrasound in petroleum desulfurization can significantly caused a reduction in the levels of sulfur. The effect of ultrasonic irradiation is attributed to the phenomena of cavitation which improve the liquid–liquid interfacial area through emulsification and then lead to a remarkable increase in solubility. .Based on earlier studies, we theorized that the application of an ultrasound to pre-treat the crude oil before the BDS process would enhance BDS efficiency of crude oil through improving the physical and chemical properties of crude oil and enhancing the mass transfer of organosulfur compounds from oil to aqueous solution. This work aims to investigate the action mechanism and ability of ultrasonic irradiation to the different sulfide in oil, study the biodesulfurization mechanism by desulfobacteria to pre-treated heavy oil by ultrasonic irradiation; Explore the mechanism coupling mechanism of biological desulfurization combined with the ultrasonic irradiation and the optimal process conditions, and then provide a new theory and method for crude oil desulfurization.

英文关键词： crude oil;biodesulfurization ;ultrasound-assisted ;mechanism