Utilization of fly ash-derived HZSM-5: catalytic pyrolysis of Jatropha wastes in a fixed-bed reactor

ABSTRACT

Fly ash-derived HZSM-5 catalyst was first applied in the catalytic pyrolysis of Jatropha residues in a semi-continuous fixed-bed reactor. The catalytic performance of HZSM-5 catalysts prepared from chemicals including conventional hydrothermal HZSM-5, Ni/HZSM-5 by ion exchange, and commercial HZSM-5 (Si/Al = 30) was evaluated for comparison. Catalytic pyrolysis of Jatropha residues with HZSM-5 catalysts was investigated in terms of product yields and qualities of bio-oil and bio-char. The liquid yield produced from fly ash-derived HZSM-5 was 29.4%, which was comparable to those obtained from chemicals and commercial (30.2–32.2%). Fly ash-derived HZSM-5 had high efficiency in increasing desirable compounds such as aliphatics and phenols as well as decreasing oxygenates and particularly N-containing compounds in bio-oils. The higher heating values and pH value of catalytic bio-oil achieved from fly ash-derived HZSM-5 were comparable to those achieved from HZSM-5 prepared from chemicals and commercial. The bio-char had 48–50 wt% carbon and was classified as mesoporous material. Overall, HZSM-5 derived from fly ash showed potentials to use as a catalyst for catalytic pyrolysis application.

KEYWORDS:

• Fly ash
• pyrolysis
• Jatropha
• bio-oil
• HZSM-5

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research is funded by the National Metal and Materials Technology Center, Thailand (Project No. MT-B-58-CER-07-308-I). This work was also supported by Grant for International Research Integration: Chula Research Scholar, Ratchadaphisek Sompoch Endowment Fund.