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Indexed by:期刊论文

Date of Publication:2008-04-01

Journal:9th China-Japan Symposium on Coal and C (1) Chemistry

Included Journals:SCIE、EI、CPCI-S

Volume:87

Issue:4-5

Page Number:508-513

ISSN No.:0016-2361

Key Words:coal liquefaction; kinetic; autoclave; heating-up; isothermal

Abstract:Direct liquefaction of Shenhua bituminous coal was carried out in a 500 ml autoclave with iron catalyst and coal liquefaction cycle-oil as solvent at initial hydrogen of 8.0 MPa, residence time of 0-90 min. To investigate the liquefaction kinetics, a model for heating-up and isothermal stages was developed to estimate the rate constants of both stages. In the model, the coal was divided into three parts, easy reactive part, hard reactive part and unreactive part, and four kinetic constants were used to describe the reaction mechanism. The results showed that the model is valid for both heating-up and isothermal stages of liquefaction perfectly. The rate-controlled process for coal liquefaction is the reaction of preasphaltene plus asphaltene (PAA) to oil plus gas (O + G). The upper-limiting conversion of isothermal stage was estimated by the kinetic calculation. (c) 2007 Elsevier Ltd. All rights reserved.