供氢剂与分散型催化剂在不同减压渣油转化中的协同作用

SYNERGISM OF HYDROGEN DONORS AND DISPERSED CATALYSTS ON CONVERSION OF DIFFERENT RESIDUES

以环烷基辽河减压渣油、中间基玉门减压渣油、克拉玛依减压渣油为进料 ,四氢萘为供氢剂 ,二烷基二硫代氨基甲酸钼为油溶性分散型催化剂 ,在高压釜中进行了裂化反应 ,比较不同基属减压渣油的加氢裂化行为。结果表明 ,在分散型催化剂作用下 ,不同基属减压渣油的加氢裂化具有不同的适应性。在生焦量相同的情况下 ,克拉玛依减压渣油的转化率高于玉门、辽河减压渣油的转化率。同时 ,供氢剂与分散型催化剂在 3种渣油的加氢裂化过程中都具有协同作用。与单独使用分散型催化剂的改质反应相比 ,供氢剂与催化剂的协同作用不但可以在低转化率下延迟生焦起初点、提高渣油生焦前的最大转化率 ,而且在高转化率下对渣油的缩合反应有更大程度的抑制作用。其中 ,供氢剂与催化剂的协同作用对环烷基辽河减压渣油的转化效果明显好于另外两种减压渣油。

Three vacuum residues of naphthenic base Liaohe vacuum residue (LHVR), intermediate base Yumen vacuum residue (YMVR) and Karamay vacuum residue (KLVR) were upgraded, taking tetrahydronaphthalene (THN) as hydrogen donor and oil soluble MoDTC as dispersed catalyst. The hydrocracking reaction systems among the three vacuum residues, e.g. vacuum residue added to hydrogen donor, vacuum residue added to dispersed catalyst, vacuum residue added to dispersed catalyst and hydrogen donor, were investigated. The relation between the coke yield and cracking yield of the three kinds of vacuum residues depends on their properties. The order of cracking yields of vacuum residues at the same coke yield is as follows: KLVR>YMVR>LHVR. There is synergism between hydrogen donors and dispersed catalysts in the hydrocracking process of the three kinds of vacuum residues. The synergism can prolong induction time of coke formation and increase the maximum conversion before coke formation, as well as can considerably improve the whole effect of deep upgrading residue. The coke formation in the deep hydrocracking process of the three kinds of vacuum residues with dispersed catalyst and hydrogen donor can be inhibited to a different degree. The synergism between hydrogen donors and dispersed catalysts on the Liaohe vacuum residue is more sensitive than on the other vacuum residues.