棉花秸秆催化热解特性及动力学的研究

Catalytic pyrolsis characteristics and kinetics of cotton stalk

通过热重分析实验观察K2CO3、KOH、KCl、NaCl、MgCl2和ZnCl26种无机催化剂对棉花秸秆热解催化效果的影响。K2CO，、KOH处理过的棉花秆与纯棉花秆相比热解发生在较低的温度范围，而KCl、NaCl、MgCl，和ZnCl2处理过的棉花秆热解发生在较高的温度范围。碱性催化剂K2C03、KOH降低了棉花秸秆的最大质量损失率，而KCl、NaCl、MgCl2和ZnCl2却增大了棉花秸秆的最大质量损失率。应用Ozawa动力学模型得到动力学参数，棉花秸秆在热解主要阶段可由一段一级反应过程描述，升温速率10K／min时活化能值EA的范围是35～66kJ／mol，频率因子自然对数的范围是4～12。

The effects of six inorganic compounds, K2CO3, KOH, KCl, NaCl, MgCl2 and ZnCl2 were investigated on pyrolysis of cotton stalk by thermal analysis. The results showed that devolatilization occurred at lower temperature as the cotton stalk was treated by K2CO3 or KOH, whereas cotton stalk samples treated with KCl, NaCl, MgCl2 or ZnCl2 devolatilized at higher temperature compare with the untreated biomass. The of cotton stalks treated with basic catalysts KOH or K2CO3 was decreased. On the contrary, the weight loss rates of cotton stalks treated with NaCl, MgCl2, KCl or ZnCl2 was increased. In addition, kinetic parameters were obtained from Ozawa-method kinetic model. The major pyrolysis process of cotton stalk can be described by one-step reaction. The range of active energy was 35 kJ/mol to 66 kJ/mol, the logarithmic frequency factor was 4 to 12.