Hydrogen-rich gas production via steam gasification of food waste over basic oxides (MgO/CaO/SrO) promoted-Ni/Al2O3 catalysts. (January 2022)

• Record Type: Journal Article
• Authors: Moogi, Surendar; Jang, Seong-Ho; Rhee, Gwang Hoon; Ko, Chang Hyun; Choi, Yong Jun; Lee, See Hoon; Show, Pau Loke; Andrew Lin, Kun-Yi; Park, Young-Kwon
• Is Part Of: Chemosphere. Volume 287:Part 2(2022)
• Publication Date: 2022-01
• Subjects: Food waste steam gasification -- Hydrogen-rich gas -- Basic oxides (MgO/CaO/SrO) promotion -- Ni/Al2O3 catalyst; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.132224
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Food waste, a renewable resource, was converted to H2 -rich gas via a catalytic steam gasification process. The effects of basic oxides (MgO, CaO, and SrO) with 10 wt% Ni/Al2 O3 on the gasification properties of food waste were investigated using a U-shaped gasifier. All catalysts prepared by the precipitation method were analyzed by X-ray diffraction, H2 -temperature-programmed reduction, NH3 -temperature-programmed desorption, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The Ni/Al2 O3 catalyst was reduced incompletely, and low nickel concentrations were detected on the surface of the alumina. The basic oxides minimized the number of acid sites and suppressed the formation of nickel-aluminate (NiAlx Oy ) phase in catalyst. In addition, the basic oxides shifted nickel-aluminate reduction reaction to lower temperatures. It resulted in enhancing nickel concentration on the catalyst surface and increasing gas yield and hydrogen selectivity. The low gas yield of the Ni/Al2 O3 catalyst was attributed to the low nickel concentration on the surface. The maximum gas yield (66.0 wt%) and hydrogen selectivity (63.8 vol%) of the 10 wt% SrO- 10 wt% Ni/Al2 O3 catalyst correlated with the highly dispersed nickel on the surface and low acidity. Furthermore, coke deposition during steam gasification varied with the surface acidity of the catalysts and less coke was formed on 10 wt% SrO- 10 wt% Ni/Al2 O3 due to efficient tar cracking. This study showed that the steam gasification efficiency of the Ni/Al2 O3 catalyst could be improved significantly by the addition of SrO. Graphical abstract: Image 1 Highlights: Hydrogen-rich fuel was produced from food waste. The degree of Ni/Al2 O3 reduction was enhanced by basic oxides (MgO, CaO, SrO). SrO-Promoted Ni/Al2 O3 produced small size Ni particles (10.9 nm). 10 wt % SrO–10 wt % Ni/Al2 O3 catalyst produced the highest H2 (63.8 vol%). Basic oxides promotion to Ni/Al2 O3 enhanced Ni dispersion and minimized coke.