Study on Useful Utlization of PSU Coal Liquefaction Residue

2001 Fiscal Year Final Research Report Summary

• Project/Area Number: 10650774
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 触媒・化学プロセス
• Research Institution: Nihon University
• Principal Investigator: MASHIMO Kiyoshi Nihon University, College of Science and Technology, Professor, 理工学部, 教授 (10059834)
• Co-Investigator(Kenkyū-buntansha): SUGANO Motoyuki Nihon University, College of Science and Technology, Assistant, 理工学部, 助手 (70256808)
• Project Period (FY): 1998 – 2001
• Keywords: NEDOL process / PSU / coal liquefaction residue / coprosessing / hydrogenolysis / supercritical water / scrap tire / oxidation

Research Abstract

The process supporting unit (PSU) constructed on the basis of NEDOL process was a 1t/d coal liquefaction plant. However, the coal liquefaction residue (CLR) was produced as by-products in about 30% yield from PSU. Therefore , the utlization of CLR as the valuable carbon resources needs to studied. The basic researches on the useful utlization of CLR were promoted from 1998 to 2001.
1. In 1998, the pyrolyses of CLR were carried out with supercritical methanol. The hexane - soluble (HS) and the acetone-insoluble were produced, with the increases of the reaction pressures (80-200kg/cm^2) and the reaction temperatures (300 - 440℃).
2. In 1999, the hydrogenolysis reaction of CLR with pulverized scrap tire was carried out by using tetralin. Compared with the result from each reaction of CLR or tire alone, the synergistic effects to upgrading, such as the increases of yields of volatile products and gases, and the decreases of asphaltene and oil materials, were observed.
3. In 2000, the pyrolyse s that used supercritical water as the reaction solvent were examined under various reaction conditions in order to attempt the conversion of CLR into hexane soluble. The effective pyrolysis of CLR to hexane soluble (oil) was realized under pressure of 270kg/cm^2 at 400℃ alone.
In addition, the upgrading reaction of pyridine soluble materials in CLR was also investigated, the increase of reactivity of CLR was found by the elimination of mineral matters, in CLR.
4. In 2001, additive effects of constituents in scrap tire on the hydrogeneolysis reaction of CLR were studied in detail. Hydrogen transfer from tetralin solvent or gas phase hydrogen to CLR was promoted by the rubber constituent in tire. As a result, the synergistic effect to upgrading was observed.
Further, the effects of the oxidation pretreatment of CLR with H_2O_2 on the subsequent hydrogenolysis reactivity of CLR were also investigated. The upgrading of CLR, such as the increase of oil yield and the decrease of asphaltene yield, was observed in comparison with that of untreated CLR.