油酸包覆型铁基催化剂及其对新疆将军庙煤与克拉玛依减压渣油低压共液化性能影响与机理研究

Industry base of large coal liquifaction is building in the region of Zhundong in Xinjiang because it's said that reserves of coal has 374.8 billion tons here. The coal from Jiangjunmiao mine located here belongs to a long flame coal with higher vitrinite. And it is explored out that Karamay oilfield contains 8.6 billion tons of cycloalkyl crude oil, where is also located in the border of the Junggar Basin. The amounts of vacuum residue oil will reach about 3～4 million t/a while the processing capacity of crude oil of Karamay enhances upon 10 million t/a in the end of Twelfth Five-Year. So this project aims at that as an object of coal from Jiangjunmiao and vacuum residue oil from Karamay, an oleic acid coated catalyst with iron-based will be prepared, the structure-activity relationship between the oil-solubility, grain size and degree of dispersion of the catalyst and its activity, key conditions, yields of oil, conversion in the processes and fractions as wells distribution in the oil-product will be investigated. And then the reaction dynamics model will be established, reaction rate constants as wells the maximum apparent activation energy and controlling step to the coal/oil co-liquefaction process will be determined. Finally the technical way and the key processing parameters will be put forward.

新疆准东煤田预测储量达到3748亿吨。凭借这一优势资源，新疆要把准东建设成为以大型煤制油为主的煤电煤化工基地。将军庙煤矿位于新疆准东煤田内，该煤属于较高镜质组分长焰煤。克拉玛依油田也地处准噶尔盆地边缘，蕴藏着86亿吨环烷基原油，原油加工能力在"十二o五"期末将超过1000万吨/年，渣油量达到300～400万吨/年。故本项目旨在以新疆将军庙煤和克拉玛依渣油为对象，制备一种油酸包覆型高分散铁基催化剂，研究环烷基减压渣油与较高镜质组煤在该催化剂作用下的共液化特性，考察催化剂活性、反应条件、煤/油共油产率和转化率，探索并掌握该催化剂的油溶性、粒度、分散度与油产率、气产率和转化率间的构效关系、煤/油共液化反应控制规律和油品馏分分布，建立其反应动力学模型，在获得主要反应的速率常数基础上，确定煤/油共液化过程的控制步骤和最大活化能，提出原则技术路线和关键工艺参数。

首先，油酸包覆型铁基催化剂（OA@Fe2O3）试样的制备、放大及其煤/油共液化催化性能考察。采用两相共沉淀法，制备了毫克级OA@Fe2O3。结果表明，制备的OA@Fe2O3试样为单分散型、粒径5-8 nm的纳米颗粒，但一次合成量仅约为70 mg。然后，对其制备过程进行了优化和逐级放大，最终实现了一次合成试样约为8 g，且放大后的试样保持单分散型和粒径5-8 nm的特点。在四氢萘/渣油/煤=1:1:1（质量比）、PH2=6 MPa、t=60 min、T=430℃和n(S)/n(Fe)=2:1液化条件下，考察克级OA@Fe2O3试样对煤/油共液化体系的催化性能影响。相对于空白试验，克级OA@Fe2O3的共液化总转化率和总油产率分别提高了5.92和16.32%，汽油和柴油产率分别提高了59.15和5.80%。.其次，采用单因素实验法，以共液化总油产率为目标，考察了克级OA@Fe2O3试样的煤/油共液化适宜工艺条件。考察结果：四氢萘/渣油/煤=1:1:1（质量比），T=400 ℃，PH2=7 MPa，t=45 min。在此条件下，共液化总油产率和总转化率分别为87.06和99.43 %。.然后，鉴于油酸钠价格昂贵，致使催化剂原料成本高。为此，改用价格相对便宜的α-烯烃磺酸（AOS）代替油酸钠。以AOS为包覆剂，在适宜的条件下，制备了AOS@Fe2O3试样，粒径为30-100 nm，并考察该试样适宜共液化条件。结果表明：在T=400℃、PH2=5MPa、t=45min和四氢萘/渣油/煤=1:1:1（质量比）条件下，总油产率和总转化率分别达到83.46和99.27%。与前者相比，后者总油产率仅降低了4.1%，而总转化率相差无几。.最后，进行了煤/油共液化动力学及其油中亚组分影响机理研究。结果表明，在煤/油共液化过程中，煤/油主要先转变为沥青烯和少量的前沥青烯，前沥青烯再转变为沥青烯。随后，沥青烯迅速转变为油和气。油中亚组分影响研究表明，随着在溶剂中芳香分或胶质添加量的增加，共液化油产率变化趋势是先增加后降低，存在着最佳添加量，即芳香分添加量达到60%时，油产率达到最大值89.07%。当胶质的添加量达到40%时，其油产率达到最大值63.33%。