双极膜电渗析处理生物质水解液的过程性能研究

Study on property of biomass hydrolysate treated by bipolar membrane electrodialysis

在由双极膜和阴离子交换膜组成的两室双极膜电渗析装置中,研究了生物质水解液糖、酸分离和酸回收的过程性能。考察了不同膜对、进料浓度、电流密度、处理室循环流量及操作温度等因素对于处理水解液过程中的电流效率和平均功耗的影响。结果表明,由BP-1双极膜与A501SB阴离子交换膜组成的膜对的性能最佳;过程的电流效率随进料液酸浓度的增大而下降,过高酸浓度的水解液进料对电渗析分离过程不利;较高操作电流密度条件下电流效率高,利于降低功耗,本装置的处理室适宜循环流量为30.0 mL/m in;操作温度的升高,对提高电流效率作用不明显,但利于降低平均功耗,本实验装置的合适操作温度为35℃。

A new bipolar membrane electrodialysis （BPED） equipment, which consists of two-compartment cell, BP （ bipolar membrane ） -A （ anion-exchange membrane） -BP （ bipolar membrane ）, was established. The separation of acid and sugar and recovery of acid （ HCl and HAc） from acidic hydrolysis of biomass was studied in this equipment. The effects of arrangement of cell pair, feed concentration, current intensity, cell cycle volume rate and operation temperature on the current efficiency and energy consumption of BPED were investigated. Results indicated that the arrangement of cell pair of BP-1 bipolar membrane and A501SB anion membrane （Tokuyama Soda） has advantages with respect to the others, regarding current density and energy consumption. Current efficiency decreases with increases acid concentration of feed increasing. Higher current density is good for lowering energy consumption and reducing the time of separation. The optimum cell cycle volume rate is of 30.0 mL/min. When operation temperature is in- creasing, the tendency to increase of current density is not obvious, but energy consumption is decrease evidently,the suitable operation temperature for the BPED equipment is at 35℃.