藏红T分光光度法测定醇醚羧酸盐初级生物降解率

Spectrophotometric Determination of Primary Biodegradation of Carboxylate of Alcohol Ether by Its Reaction with Safranine T

以碱性藏红T溶液作为指示剂,在pH8.6的硼酸-硼砂缓冲溶液中,三氯甲烷为萃取剂,采用紫外可见分光光度法对醇醚羧酸盐(AEC)进行了研究。结果表明:无表面活性的磷酸盐、乙酸盐以及常用的Cl^-、HCO_3^-和SO_4^(2-)对体系无影响,而具有表面活性的十二烷基硫酸钠和烷基苯磺酸钠对体系具有明显的影响,导致吸光度增大。方法检出限(3s)为0.2mg·L^(-1)。对醇醚羧酸盐的初级生物降解研究表明,即使醇醚羧酸盐(含有9个乙氧基)的质量浓度为100mg·L^(-1)时,24h的降解度达到95%以上;醇醚羧酸盐具有好的生物降解性能,在自然条件下能完全生物降解。

In a borate buffer medium of pH 8.6,a hydrophobic association complex was formed by the reaction of the anion of carboxylate of alcohol ether（AEC） with cation of the reagent safranine T,and the reaction product was extracted with trichloromethane and its absorbance was measured at the wavelength of 519 nm.Based on this color reaction,the primary biodegradation of AEC was studied.Detection limit（3s） of the reaction in respect to AES was found to be 0.2 mg·L^（-1）.Those anions,i.e.acetate,Cl^-,HCO_3^- and SO_4^（2-）,showed no interference to the above mentioned reaction,but the anionic surfactants of SDS and LAS showed obvious influence of increasing the absorbance significantly.As shown by the experimental results,the degradation rate of AEC_9 in a solution having its mass concentration as high as 100 mg·L^（-1）,under natural condition achieved to a value of 95%after 24 h,and it was proved that AEC showed excellant primary biodegradation property.