耐辐射奇球菌R1对Mn^(2+)清除作用研究

Effects on the Removal of Mn^(2+) from Aqueous Solution by Deinococcusradiodurans R1

观察耐辐射奇球菌(Deinococcusradiodurans)R1在不同作用条件下对溶液中Mn^(2+)的清除作用,为进一步研究R1清除放射性废水中的Mn^(2+)奠定基础。采用原子吸收分光光度法分析了作用时间、温度、pH值、初始接菌浓度和初始Mn^(2+)浓度对R1菌清除溶液中Mn^(2+)的影响。结果显示,活的R1菌对Mn^(2+)的有较好的清除效果,而死R1菌对Mn^(2+)没有清除能力;作用时间(0.5～48 h)对Mn^(2+)的清除率影响不大,相对较适作用时间为2～4 h,随着环境温度增高,R1菌对溶液中Mn^(2+)的清除率增加,相对较适温度为30～45℃时;p H低于4不利于R1对Mn^(2+)的清除,p H 5～10时,对R1菌清除Mn^(2+)影响不大,最适p H值为5～8;初始Mn^(2+)浓度相同时,加入R1量越多,清除率越高,但单位质量的R1对Mn^(2+)的吸附量越少;初始R1量相同时,加入Mn^(2+)浓度越高,清除率越低,最后随着Mn^(2+)浓度增高,R1清除Mn^(2+)的能力达到饱和,R1对Mn^(2+)的饱和清除量为1.35 mg/g。结果表明,在适当的温度和p H环境中,活的R1菌在较短作用时间内对溶液中Mn^(2+)就有较好的清除作用(>90%),R1菌在放射性核素污染防治方面具有潜在的应用前景。

To investigate the effects on the removal of Mn^(2+) from aqueous solution by Deinococcusradiodurans R1 under different conditions. The influence of multi-factors, such as temperature, p H, time, initial concentration of bacteria( C_m) and initial Mn^(2+)concentration(C_0) in solution, on the removal of Mn^(2+)using R1 was assayed by atomic absorption spectrometry.The removal effect of Mn^(2+)by living R1 was very high, but dead R1 showed no removal effect of Mn^(2+). The time(0.5 to 48 h)and p H(5～10) had little effect on the removal rate, but the removal rate was remarkably decreased when p H value was lower than 4.The temperature had a certain influence on the removal rate, and the removal rate increased with the increase of tem-perature and was at the plateau stage 30～45 ℃. The optimum temperature was 30～45 ℃, the optimum time was 2～4 h, and the optimum p H value was 5～8. In a certain of Mn^(2+)concentration, the removal rate of Mn^(2+)by R1 increased with the increase of C_m, but the quantity of removed Mn^(2+)by a unit mass R1 was reduced with the increase of C_m. In a certain of R1 concentration, the removal rate of Mn^(2+)by R1 reduced with the increase of C_0, and the removal value of Mn^(2+)by R1 reached saturated1.35 mg/g. The results showed that R1 had good removal effects on Mn^(2+)from solution in the short action time(>90%), and strong environmental adaptability to temperature and p H etc. Therefore, Deinococcusradiodurans R1 has a potential application prospect in the aspects of radioactive pollution control.