Study On The Gasification Of Bamboo Chips Catalyzed By Red Mud Supported Nickel Catalys

How to improve the efficiency of biomass steam gasification and obtain more hydrogen-rich syngas is the research hotspot of energy structure transformation.Adding catalyst is an effective way to improve gasification activity and gas production efficiency.In this study,red mud supported nickel catalyst（Ni/RM）was prepared by using bamboo sawdust（BS）as raw material and Bayer red mud（RM）as catalyst carrier to improve the gasification efficiency of BS.In this paper,the pyrolysis characteristics,pyrolysis kinetics,gasification characteristics and Ni/RM catalytic mechanism of BS were studied.The main reports are as follows:（1）The effect of pyrolysis temperature on the pyrolysis characteristics of BS was studied in a fixed bed reactor.The BS pyrolytic carbon at different pyrolysis temperatures was characterized by scanning electron microscopy（SEM）,Raman spectroscopy（Raman）and infrared spectroscopy（FT-IR）.The results show that high temperature will destroy the molecular structure of biomass,resulting in increased gas production and increased carbon structure order.（2）By comparing the thermogravimetric curves（TG）and weight loss rate curves（DTG）of BS at different heating rates,the pyrolysis weight loss characteristics of BS at different heating rates were clarified,and the kinetic parameters of BS pyrolysis were calculated.The results show that the pyrolysis process of BS includes three stages:drying,pyrolysis and carbonization.The activation energy of pyrolysis reaction is 59.9 k J·mol^-1,and the frequency factor is 4.16×10⁵ min^-1.（3）The effects of deionized water flow rate,temperature and catalyst on BS gasification characteristics were investigated in a fixed bed reactor.The results showed that when the flow rate of deionized water was 0.25m L·min^-1 and the gasification reaction temperature is 850°C,the gas production of BS gasification is the highest,and the catalytic activity of alkali metal catalyst is the best.（4）The effect of Ni/RM on the gasification characteristics of BS was studied,and the catalytic mechanism of Ni/RM was discussed.The results show that the addition of Ni/RM increases the H₂ yield by 43.8%compared with BS gasification alone.The high catalytic activity of Ni/RM is attributed to the interaction of Ni,Fe and Mg elements to form Ni Fe₂O₄,Mg Ni O₂ and Ni O components with good catalytic effect on tar conversion.During the gasification process,the oxidation of water vapor and the reduction of H₂ and CO promoted the cyclic transformation of the active component between the oxidized state and the reduced state,and Ni/RM showed good stability.