UV-H2O2及UV-O3工艺降解水中微囊藻毒素-LR

THE DEGRADATION OF MICROCYSTIN-LR IN WATER BY UV-H_2O_2 AND UV-O_3 PROCESSES

对2种高级氧化工艺（UV-H2O2、UV-O3）降解水体中微囊藻毒素-LR（MC-LR）进行研究。结果表明,相比于单独UV、H2O2和O3工艺,2种组合高级氧化工艺有更高的氧化效率。在UV-H2O2工艺中,增加H2O2与MC-LR初始摩尔比至1 000：1,5 min后此工艺可去除99.5%的MC-LR;继续提高H2O2投加量,工艺效果受抑制。在UV-O3工艺中,在O3与MC-LR的初始摩尔比为3：1的条件下,反应30 s后即可去除高于99.5%的MC-LR。在p H为3-10时,p H对UV-H2O2工艺效果影响不显著,而较低p H可以促进UV-O3工艺降解MC-LR。较高DOC含量可显著抑制2种工艺的效率。对主要降解产物的结构分析表明,UV-O3工艺比UV-H2O2工艺更容易破坏MC-LR的分子结构。

The performances of two advance oxidation processes （UV-H2O2, UV-O3） for the degradation ofmicrocystin-LR （MC-LR） were investigated. Results showed that UV-H2O2 and UV-O3 had better performances to remove MC-LR from water, compared with UV-, H2O2- and O3-alone process. During UV-H2O2 process, more than 99.5% of MC-LR could be degraded within 5 min of the reaction when the initial molar ratio of H2O2 to MC-LR increased to 1 000：1. However, the.efficiency of UV-H2O2 was inhibited if the initial H2O2 content fiarther increased. For UV-O3 process, more than 99.5% of MC- LR could be degraded after 30 s of the reaction when the initial molar ratio of O3 to MC-LR was 3. The pH had insignificant influence on the efficiency of UV-H2O2, but lower pH could promote the degradation of MC-LR by UV-O3. High DOC concent could significantly decrease the efficiency of the two processes. The identification of reaction products of MC-LR showed that UV-O3 process was prone to destroy the structure of MC-LR.