用电渗析和离子交换相结合的方法处理印制电路板氯化铜废水

据统计,我国有近千家生产印制电路板的工厂。在生产过程中,大量被刻蚀下来的铜离子随废水排放。一个年产20万m~2电路板的小型工厂,一年内就要排放掉近30t铜。这不仅浪费了铜,而且严重地污染了环境。因此,治理刻蚀工艺含铜废水具有现实意义。 传统的中和沉淀法处理刻蚀工艺含铜废水投资高、占地面积大、耗用大量化学试剂;该法处理过的水含盐量(尤其C1~-)高,不能直接回用。     

膜电解氢自养MBBR反应器深度转化水中高氯酸盐

建立膜电解电化学氢自养MBBR反应器（移动床生物膜反应器）用于去除水中高氯酸盐,微生物利用阴极电解产生的氢气将高氯酸根还原为氯离子,而后氯离子在阳极发生氧化析氯反应生成活性氯进一步提升出水水质,从而实现高氯酸根的深度转化.利用该反应器研究了高氯酸根的转化过程及相关影响因素,结果表明：进水ClO₄^-浓度为（4.98±0.091）mg/L,维持HRT（水力停留时间）为4h,施加电流由6mA增加至15mA,反应器对高氯酸根的去除率由（39.75±2.09）%增加至（98.99±0.05）%,总出水活性氯浓度由（0.057±0.003）mg/L增加至（0.070±0.002）mg/L,pH值稳定在7.96~8.11,浊度较低为（0.89±0.27）NTU.进一步增大施加电流（20mA）,导致阴极室溶液pH值超过9.5,进而影响微生物活性,去除率急剧下降至（30.75±1.19）%.利用扫描电子显微镜（SEM）观察反应器内微生物形貌,发现反应器内微生物均附着于填料表面,以短杆菌为主,增殖缓慢.运用高通量测序技术对接种及运行第24d的微生物群落结构展开分析.结果显示,反应器运行过程中,菌群多样性下降,Thauera菌属为主要的氢自养还原优势菌属,其丰度达到8.25%.     

Energy conversion from electrolyte concentration gradient using charged nano-pores

Power generation based on the reversed electro-dialysis (RED) cell is studied both numerically and experimentally in this work. The membrane that separates the concentrated and dilute electrolytes is treated as a charged nano-pore array. Both numerical and experimental results show that the RED cell performance is similar to the typical electrochemical cell having a linearly varied current–voltage relation. The open circuit voltage and short-circuit current depend on the ion selectivity of the nano-pore membrane, which is related to the concentration ratio, pore surface charge density, and pore size. The highest energy conversion efficiencies are approximately 48% and 24% from numerical predictions and experimental measurements, respectively. The reason for this discrepancy is attributed to the inhomogenous pore size and surface charge density distributions of the Al₂O₃ membrane used in these experiments.