A study into syngas production from catalytic steam reforming of palm oil mill effluent (POME): A new treatment approach

• Published in: International journal of hydrogen energy 2019-08, Vol.44 (37), p.20900-20913
• Main Authors: Ng, Kim Hoong, Cheng, Yoke Wang, Lee, Zhan Sheng, Cheng, C.K.
• Format: Article
• Language: English
• Subjects: Palm oil mill effluent; Steam reforming; Syngas; Waste treatment
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2018.04.232

This paper reports on the novel application of catalytic steam reforming process to convert palm oil mill effluent (POME) into syngas over a 20wt%Ni/80wt%Al2O3 catalyst. The catalyst possessed high degree of crystallinity and was impurity-free, judging from the obtained XRD pattern. Furthermore, the BET specific surface area of catalyst was low (2.09 m2 g−1), consistent with smooth surface captured by the FESEM images. CO2-desorption and NH3-desorption profiles showed a presence of both acid and basic sites on the surface of catalyst. In the absence of catalyst, about 7.0% reduction of chemical oxygen demand (COD) was achieved at 6.0 mL h−1 flow rate of POME, reforming temperature of 873 K and 20 mL min−1 of N2-flow. Significantly, the COD reduction shot up to 93.7% in the presence of catalyst and liquid-hourly-space-velocity (LHSV) of POME of 90 mL h−1 gcat−1 at 873 K. The corresponding biochemical oxygen demand (BOD) reduction recorded was 93.8%. However, normalized carbon loss indicates that a high LHSV would favour carbon deposition. In addition to high LHSV, the carbon deposition was also influenced by reaction temperature. High reaction temperature has reduced carbon deposition, as well as organics removal. COD reduction was 99.41% and BOD reduction was 99.52% at 1173 K when LHSV was 60 mL h−1 gcat−1. In the gas phase, four species were consistently detected, viz. H2, CO2, CO and CH4, with H2 as the major component. The H2 selectivity increased with both LHSV and reaction temperature. •More than 99% of organics in POME was degraded in the presence of catalyst.•The H2 selectivity increased with both LHSV and reaction temperature.•Carbon deposition was reduced at elevated reaction temperature.