Study On The Effect Of Compound Adjuvant On Slurry-Bed Hydrocraking For Residue

The compound adjuvant together with water-soluble catalyst were added into LHAR. The effect of representative Non-ionic, Anionic and Cationic surfactants compound to reaction was investigated in a magnetic-stirred autoclave.The study focused mainly on the result of coke-formation. The way and the proportion of compound were selected in detail, the further study was made on the satisfactory results, and the products distribution was investigated in the different reaction temperature, reaction time and concentration of additives.The effect of proportion and concentration compound additives(SA) on reaction were investigated. The experimental results showed that the coke-formation of slurry bed hydrocracking was the smallest when the compound of SAP1 and SAN1 was added with the proportion of 1/1. The results also showed that with the increase of SA's concentration, the coke-formation increases first, and then decreases, and the optimum concentration of SA was 300μg?g-1.The effect of compound adjuvant on the colloidal properties of residue and on the catalyst dispersion were investigated in order to study the mechanism of adjuvant affecting the slurry-bed hydrocracking of residue. The results showed that during the process of reaction, the compound adjuvant could decrease the CSP of residue system, increase the average molecular weight of asphaltene and the number of asphaltene with more rings and higher condensation degree. It showed that compound adjuvant could improve the colloidal stability of residue effectively, resist the aggregation of asphaltene and postpone the appearance of second liquid-phase. The results also proved that compound adjuvant could improve the effect of catalyst dispersion by reducing the surface tension of aqueous solution of catalyst. It can reduce the granularity of catalyst particles, increase the surface area of catalyst, and make the coke particles in liquid product more regular, the granularity of coke smaller and surface of coke looser. Moreover, it could obtain from the IR spectra of compound adjuvant that the inter-strong electrical energy between cation-anion adjuvant could promote the formation of complex in the aqueous solution of catalyst which could form special space structure to restrain the farther aggregation of asphaltene.