Method for adjusting and controlling heavy oil molecular structure

Abstract

The invention relates to a method for adjusting and controlling the heavy oil molecular structure. Supercritical benzene in a specific thermodynamics state and a mesoporous molecular sieve are introduced into the shallow catalytic cracking of heavy oil. By dissolving the heavy oil in the supercritical benzene in the specific thermodynamics state, the diffusion coefficient D of heavy oil moleculescan be easily improved; by means of the mesoporous molecular sieve, the adverse effects of diffusion blocking factors F(dr / d) on the diffusion of the heavy oil molecules in catalyst ducts are furtherrelieved. Thus, the diffusion cover of the carbon positive ion mechanism catalytic cracking of the heavy oil is converted into reaction kinetics control which can be smoothly conducted at a low temperature. Through the measures, the breakage of aromatic alkyl side chains or links of heavy oil molecular structure adjusting and controlling is more rapidly decided, cracking is controlled at a properdepth on the basis of the optimization of the technological conditions. Moreover, thick cyclization is restrained and no coke is generated. The processed product can be used for subsequent catalytic hydrogenation or transport property improvement.

Description

technical field [0001] The invention relates to the technical field of heavy oil, in particular to the treatment of heavy oil, in particular to a method for regulating the molecular structure of heavy oil. Background technique [0002] Heavy oil including extra heavy crude oil, oil sand bitumen, vacuum residue, atmospheric residue, and catalytic cracking slurry has the following properties: figure 1 Similar molecular structure features are shown: 1) there is a complex fused ring center composed of aromatic rings, cycloalkane rings and heterocycles; 2) there are alkyl side chains or links in the fused ring center. Such as figure 1 The structural features shown make the average scale of heavy oil molecules (d r ) are generally large and the viscosity (μ) is extremely high. [0003] The structural characteristics of heavy oil molecules bring serious problems to heavy oil transportation and catalytic processing. For heavy oil transportation, it has clear index requirements f...

AI Technical Summary

Problems solved by technology

Even if the optimum airspeed disclosed by the patent is 40~50h -1 It is helpful to suppress the condensation of free radical mechanism from the reaction kinetics, but in the description of the process characteristics, there is still the conclusion that "a small amount of solid coke is formed on the catalyst", which is obviously not conducive to the stable operation of catalytic cracking

Images