Enhanced hydrogen production via staged catalytic gasification of rice husk using Ca(OH)2 adsorbent and Ce–Ni/γAl2O3 catalyst in a fluidized bed. (22nd May 2023)

• Record Type: Journal Article
• Authors: Zeng, Xi; Fang, Mengxiang; Shan, Yidan; Lv, Tong; Cen, Jianmeng; Wang, Qinhui; Wang, Kaige
• Is Part Of: International journal of hydrogen energy. Volume 48:Number 44(2023)
• Page Start: 16630
• Page End: 16648
• Publication Date: 2023-05-22
• Subjects: Hydrogen production -- Rice husk -- Staged catalytic gasification -- Ca(OH)2 adsorbent -- Ce–Ni/γAl2O3 catalyst -- Fluidized bed; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.12.218
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Hydrogen production from rice husk was carried out via a two-stage system combining CLG (calcium looping gasification) using Ca(OH)2 adsorbent in a bubbling fluidized bed and catalytic reforming with Ce–Ni/γAl2 O3 catalyst in a connected fixed bed. The results show that the maximum H2 concentration (69.16 vol%) and H2 yield (11.86 mmol g −1 rice husk ) are achieved at Ca/C (Ca(OH)2 to carbon molar ratio) = 1.5, H2 O/C (H2 O to carbon molar ratio) = 1.5, Tg (gasification temperature) = 500 °C, Tc (catalytic temperature) = 800 °C. The supplementation of fresh Ca(OH)2 at Ca/C of 0.5 during calcination helps to activate the regenerated CaO by hydration, maintaining its carbonation activity and CO2 adsorption. Ce–Ni/γAl2 O3 catalyst promotes water gas shift (WGS), steam methane reforming (SMR), and C2 –C3 hydrocarbons reforming, also exhibits excellent activity stability to maintain H2 concentration and H2 yield above 67.21 vol% and 11.67 mmol g −1 rice husk, respectively, during 5 lifetime tests. Highlights: Staged catalytic gasification of rice husk in a fluidized bed for H2 -rich gas. Ca(OH)2 adsorbent promotes WGS and hydrocarbons reforming at a moderate temperature. Fresh Ca(OH)2 supplement during calcination activates regenerated CaO by hydration. Ce–Ni/γAl2 O3 catalyst promotes WGS, SMR, and C2 –C3 hydrocarbons reforming reactions. Ce–Ni/γAl2 O3 catalyst shows excellent activity stability with low carbon deposition. Graphical abstract: Image 1