Abstract:

A solid electrode with Cu(Ⅱ) was prepared by utilizing chitosan modified electrode to adsorb Cu(Ⅱ) in the solution, which was used as the cathode of microbial anode and chitosan modified cathode based battery (MACMCB). Different Cu(Ⅱ) masses and external loadings were tested to study the discharge property of MACMCB system. Results indicate that better discharge process relies on a larger amount of Cu(Ⅱ) or a higher external loading in this work. The highest cell voltage is 0.6346 V. The Cu(Ⅱ) reduction efficiency of MACMCB system is higher than 92.75%, indicating a nearly complete reduction of Cu(Ⅱ). The comparison between MACMCB and MFC indicates that MACMCB showes better performance than MFC on substrate consume and electricity output within a period of time. Changing the solid electrode within 10 - 30 hours is recommended. CuSO₄ is directly adsorbed inside the solid electrode. The major reduction product is copper, while the left included Cu₂O, phosphide of copper and chloride of copper.

Key words: solid electrode with Cu(Ⅱ), MACMCB, Cu(Ⅱ) reduction, electricity generation, substrate consume

摘要：

采用壳聚糖修饰电极吸附溶液中 Cu(Ⅱ)制得含铜固体电极, 将其用做新型无膜生物电化学系统(MACMCB)阴极。研究固体电极 Cu(Ⅱ)质量和外阻对 MACMCB 电压的影响。结果表明, 系统电压与含铜固体电极 Cu(Ⅱ)质量及系统外阻正相关, 最大输出电压达 0.6346 V。该系统 Cu(Ⅱ)还原效率高于 92.75%, 表明 Cu(Ⅱ)做电子受体得电子能力强, Cu(Ⅱ)几乎被全部还原。MACMCB 与微生物燃料电池(MFC)的效率对比结果表明, 在一定时间内, MACMCB 在底物降解效率和产能输出方面明显优于 MFC, 推荐含铜固体电极更换时间为 10~30 小时。含铜固体电极中 Cu(Ⅱ)主要以 CuSO₄ 分子形式存在, 放电后 Cu(Ⅱ)的主要还原产物为单质Cu, 含少量Cu₂O, 另外掺杂部分Cu元素的磷化物和氯化物沉淀。

关键词: 含铜固体电极, 新型无膜生物电化学系统, Cu(Ⅱ)还原, 生物产电, 底物降解