Enhancement of hydrogen production by secondary metal oxide dopants on NiO/CaO material for catalytic gasification of empty palm fruit bunches

• Published in: Energy (Oxford) Vol. 47; no. 1; pp. 158 - 165
• Main Authors: Taufiq-Yap, Y.H., Sivasangar, S., Salmiaton, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.11.2012; Elsevier
• Subjects: absorption; adsorption; agricultural wastes; Applied sciences; Biomass; burning; calcium oxide; CaO; carbon dioxide; Catalysis; Catalysts; cobalt; Dopants; EFB; Energy; Exact sciences and technology; feedstocks; fossil fuels; gases; Gasification; greenhouse gas emissions; hydrogen; Hydrogen production; Iron; nickel; nitrogen; nonrenewable resources; oxygen; Palm; renewable energy sources; spectrometers; temperature; thermogravimetry; X-ray diffraction; EFB; CaO; Dopants; Gasification; Hydrogen production
• ISSN: 0360-5442
• DOI: 10.1016/j.energy.2012.09.026

The increase of fossil fuel burning to meet massive energy demands has resulted in major environmental problems. Extensive green house gas emissions and the depletion of non-renewable resources have promoted the use of hydrogen as an alternative energy source. Empty palm fruit bunches (EFB) are a type of agricultural waste that have a high potential for use as a sustainable biomass feedstock for hydrogen production. This study is focused on generation of biomass-derived hydrogen through catalytic biomass gasification using a modified CaO-based catalyst. The catalyst was prepared by adding 5% Ni as a primary dopant, followed by the addition of secondary dopants (La, K, Co, Fe) through a wet impregnation method, and characterised by X-ray diffractometer (XRD), N2 adsorption (BET) and Thermogravimetric Analysis (TGA). The synthesised catalysts were used as the primary catalysts in the reaction and were tested in temperature programmed gasification (TPG). The reaction was carried out in a partial oxygen environment by incorporating the biomass with the catalyst in a ratio of 1:2 from 50 to 900 °C and the product gases were detected by an online mass spectrometer. Interestingly, the addition of secondary dopants significantly increased the hydrogen production with notable changes in the CO2 absorption capacity of the catalyst. Moreover, K, Co and Fe dopants showed tar reforming properties and the highest hydrogen yield was observed with K as the added catalyst. ▸ Describe about CaO modification with primary and secondary dopants. ▸ Discuss the effect of secondary dopants on Tar cracking and CO2 absorption of the CaO catalyst. ▸ Identified the dopants that promote tar cracking and reforming reaction favour to H2 production.