【摘要】 探讨在添加或不添加NaN₃条件下,不同周丛生物投放量（干质量0.1、0.2、0.3、0.4 g/L）,温度（10、15、20、25、30、35℃）,pH（4、6、8、10）和起始罗丹明B质量浓度（1、5、10、20、40、80、160 mg/L）对周丛生物对罗丹明B的吸附和降解特性的影响,并通过HPLC–MS分析周丛生物对罗丹明B的降解机理。结果表明:周丛生物对罗丹明B具有一定的吸附和降解能力,在本试验周丛生物的用量范围内,随着用量的增加,周丛生物对罗丹明B的去除率逐渐增加;其过程主要是2阶段的协同过程,涉及生物吸附和生物降解,以吸附为主;不添加NaN₃的周丛生物去除罗丹明B的最佳pH为6,温度为30℃;添加NaN₃的周丛生物对罗丹明B的最佳吸附pH为6,温度为20～30℃;等温线以Langmuir模型和Freundlich模型拟合,周丛生物+NaN₃组更符合Langmuir模型;HPLC–MS检测结果表明,周丛生物降解罗丹明B产生1个相对分子质量约为391的中间产物,其降解过程可能是一个逐步脱乙基的过程。更多还原

【Abstract】 This study investigated the adsorption and degradation characteristics of rhodamine B（RhB） by periphyton with or without NaN₃, under a group of the dosage of periphyton（dry mass 0.1, 0.2, 0.3, 0.4 g/L）, temperatures（10, 15, 20,25, 30, 35 ℃）, pH values（4, 6, 8, 10） and the initial mass concentration of RhB（1, 5, 10, 20, 40, 80, 160 mg/L）. This study also investigated the degradation mechanism of RhB by periphyton with HPLC-MS detection. The results showed that periphyton had some functions in biosorption and degradation of RhB. Within the dosage of periphyton in this experiment, the removal rate towards RhB increased gradually with the raise of periphyton. The removal procedure of RhB by periphyton included two-stage synergistic processes, involving biosorption and biodegradation, with biosorption as the dominant process. The optimal pH and temperature for removal of RhB by periphyton without NaN₃ were 6 and30 ℃, respectively; the optimal pH and temperature for adsorption of RhB by periphyton with NaN₃ were 6 and 20-30 ℃,respectively. The isotherm was fitted by the Langmuir model and the Freundlich model, meanwhile, the Langmuir model was more suitable in explaining the adsorption isotherm of RhB by periphyton with NaN₃. The results of HPLC-MS detection showed that the degradation of RhB might produced an intermediate product with a molecular weight of about391 and the degradation process involved a gradual deethylation.更多还原