Kinetics of coke formation from coal solutions

✍ Scribed by Terry D. Rantell; James W. Clarke

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 489 KB
• Volume: 57
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(78)90066-2

✦ Synopsis

The reaction kinetics for the formation of mesophase from coal solutions has been studied under conditions similar to those experienced in a delayed coker preheater coil, i.e. at temperatures from 475 to 525°C approached at high heating rates. The degree of polymerization of the heat-treated materials has been assessed by their solubility in two solvents, cyclohexane and quinoline. An approximation has been made in order to make a kinetic analysis for the formation of insolubles in a non-isothermal system. It has been found that the polymerization of the dissolved coal component, as evidenced by the formation of quinoline insolubles during the heat-treatment of concentrated coal solutions, is essentially a second-order reaction with an apparent activation energy of z190 kJ mol-'. The formation of cyclohexane insolubles from the diluent oil is a slower reaction showing first-order kinetics.