基于SnO2/Sn/CH4两步法生产太阳能燃料的热力学研究

Thermodynamic the production of solar fuel based on SnO_(2)/Sn/CH_(4) two-step process

SnO_(2)/Sn甲烷还原及水分解的太阳能燃料转换方法,有还原温度低、燃料选择性高、操作范围广的特点。运用HSC化学热力学软件对SnO_(2)/Sn甲烷太阳能燃料化的循环进行了计算与分析,研究了还原温度、反应物配比、还原反应器中气体压力对生成物质组分、燃料能量升级因子和能量转换效率的影响。结果表明,CH_(4)的引入可降低SnO_(2)的还原温度,还原温度高有利于反应进行;高压力(p)使SnO_(2)还原温度提高并降低能量升级因子及太阳能燃料转换效率;温度低有利于水氧化反应的进行,过大的X(H_(2)O/Sn摩尔比)会降低太阳能燃料转化效率。在p=0.1 MPa,R=2,X=2,T red=1260℃,T oxi=25℃时可获得最大的太阳能燃料转化效率0.50。

The two-step solar thermal chemical cycle solar fuel conversion method based on SnO_(2)/Sn methane reduction and water decomposition has the characteristics of low reduction temperature,high fuel selectivity,and wide operating range.The thermodynamic calculation and analysis of the thermochemical cycle of SnO_(2)/Sn methane solar fueling are carried out using HSC chemical thermodynamics software,the effects of redox temperature,reactant ratio and gas pressure in the reduction reactor on the balance of material components,fuel energy upgrading factor and energy conversion efficiency were studied.The results show that the introduction of CH_(4) can lower the reduction temperature of SnO_(2),high temperature is beneficial to the reduction reaction,high pressure p increases the reduction temperature of SnO_(2) and reduces the energy upgrade factor and solar fuel conversion efficiency;low temperature is beneficial to the progress of water oxidation reaction.Excessive X(H_(2)O/Sn molar ratio)will reduce solar fuel conversion efficiency.When p=0.1 MPa,R=2,X=2,T red=1260℃,T oxi=25℃,the maximum solar fuel conversion efficiency of 0.50 can be obtained.