Study On Preparation Of Needle Coke From Co-carbonization Of FCCDO And HCGO

Needle coke production lacks in right feed-stocks at present. In this thesis, fluid catalytic cracking decant oil (FCCDO) and heavy coker gas oil (HCGO) which are all from JinZhou Petrochemical Co. were taken as testing samples and thermally pretreated to investigate needle coke formation, aiming at developing methods for producing needle coke from FCCDO or FCCDO mixed with HCGO Reaction temperature and reaction pressure are very important factors affecting carbonization/co-carbonization, and needle coke formation, so the kinetics of the formation of toluene insolubles(TI) and pyridine insolubles(PI) was systematically studied.In this thesis, a polarized-light microscopy was used to determine the quality of the coke. Measuring the volume of the gas produced during the reaction under different temperature was completed to study its connection with coke quality. It was found that the optimum condition for the carbonization from the two feed-stocks above is 480℃and 0.6MPa. On this optimum conditions, the optical texture of the coke takes an elongate flow domain structure and good ordered regions . The residues of carbonization was separated into four fractions that were heptane solubles(HS),toluene solubles(TS),pyridine solubles(PS) and pyridine insolubles(PI) by the method of sequential solvent extractions. The solvents used were heptane(H), toluene(T)and pyridine(P). The results are as follows: The early stages of the condensation reactions of the carbonization, involved a fast dealkylation process of the long aliphatic side-chains. The transition from HS to TS was the main dealkylation process. Changes in solubility resulted from increases in molecular weight and the degree of condensation was increased from HS to PI. The conversion of HS to PI was occurring according to the following scheme: HS→TS→PS→PI. Results indicated that their activation energies of first order reaction from FCCDO were 153 kJ/mol and 185 kJ/mol, their activation energies of second order reaction were 177kJ/mol and 209kJ/mol, respectively, and their activation energies of first order reaction from the mixed feed-stoke of FCCDO and HCGO were 122 kJ/mol 144 kJ/mol, their activation energies of second order reaction were 131kJ/mol and 145kJ/mol, respectively.