固定化蒽醌对偶氮染料生物降解促进作用研究

Accelerating Effects of Immobilized Anthanquinone on the Anaerobic Biodegradation

采用非水溶性蒽醌固定化技术对偶氮染料生物降解促进作用进行了研究,对比了海藻酸钙,聚乙烯醇-硼酸,聚乙烯醇-海藻酸钙和琼脂4种固定化技术,探讨了溶解氧对脱色过程的影响和固定化蒽醌系统脱色广谱性.研究结果表明,固定化蒽醌可提高多种偶氮染料生物厌氧脱色速度1.5~2倍和降低偶氮染料脱色过程氧化还原电位-10^-15 mV;经4次循环使用后,其加速作用仍保持在90%以上;固定化蒽醌微生物系统具有很强抗氧冲击能力.

The accelerating effect of anthanquinone as a redox mediator in the bio-decolorization was conducted. Decolorization of azo dyes was carried out experimentally using the salt-tolerant bacteria under immobilized anthanquinone and high salt conditions. Anthnaquinone used as a redox mediator was able to increase the decolorization rate of wastewater containing azo dyes, and was immobilized by entrapment in calcium alginate （CA）, polyvinyl alcohol （PVA）-H3BO3, polyvinyl alcohol （PVA）-caleium alginate （CA） and agar, respectively. The effects of various operating conditions such as anthnaquinone bead number and dissolved oxygen on microbial decolorization were investigated experimentally. At the same time, immobilized anthanquinone was tested to assess the effects on the change of the oxidation-reduction potential （ORP） values during the decolorization processes. High decolorization rate was obtained in the presence of 200 anthnaquinone immobilization beads at 30℃, which increased 1.5-2 fold, in comparison with the control of free-anthanquinone. The oxidation-reduction potential （ORP） values stabilized around - 260- - 265 mV after 6 hours anoxic conditions, which lowered ORP values around - 10 - - 15 mV by anthanquinone. The reusability of the anthnaquinone immobilization beads was evaluated with repeated-bacth decolorization experiments. After four repeated experiments, the decolorization rate of calcium alginate （CA） immobilized anthnaquinone retained over 90% of their original activity.