Study On Oxidation Degradation Of Dianilino Dithiophosphoric Acid Using Ozone

Our country has rich miner resources, more than thousands of tons waste water has been generated as a result of mineral processing. Floatation is the most common mineral processing method for metal sulfide ore, and dianilino dithiophosphoric acid, which commonly known as aniline aerofloat, is one of the most commonly use floatation collecting agents for metal sulfide ore. Aniline aerofloat is regarded as refractory organics, the residual aniline aerofloat, which leads to a higher CODCr, is hard to be purified using regular methods. Ozone oxidation process, as one of the high efficient oxidations, is usually used for high chroma, high concentration and refractory organic waste water treatments.This thesis has studied the process of aniline aerofloat oxidated by ozone in the simulated waste water, using ozone as oxidants and aniline aeorfloat as target pollutant. In the meanwhile, this thesis has also studied the factors which have influences on ozone oxidation degradation, established a dynamical model for the degradation process, and analyzed the aniline aerfloate ozone oxidated products.There are difficulties involved when determining the concentration of aniline aerofloat. Firstly, this thesis has developed HPLC to measure the concentration of aniline aerofloat in the water liquor directly, and depicted a standard curve with the concentration of aniline aerofloat from12mg/L to30mg/L. The results indicate that, with the optimizing factors like mobile phase, this method has the following advantages:it has a good linear relation when the concentration is between12mg/L and300mg/L, the relative coefficient R2is0.9999; it has good precision and accuracy, with RSD<3%.Additionally, this thesis has studied the conditions and results of ozone oxidating aniline aerofloat in the simulated waste water. It has mainly tested the effects of ozone oxidation time, system’s initial pH value and reaction temperature, etc. The results show that, when applying5g/h ozone oxidating to the waste water with initial aniline aerofloat concentration rates50mg/L,75mg/L and150mg/L for20minutes, the degradation rates are100%,99%and88%, and the CODCr removal rates are56%,59%and76%respectively, and the corresponding oxidation kinetics of the apparent first-order rate constant k is-0.259s-1、-0.331s-1and-0.372s-1:R is0.9903、0.9949and0.9926. After the reaction, the pH of the waste water changed from its intial6.58-7.67to strong acid (<4), which analysed the mechanism of pH variation before and after the reaction. During the reaction process, the colour of the waste water changed from transparent to claybank, and then gradually changed to yellow, faint yellow, and eventually back to transparent.At last, utilised PTC-GC/MS and HPLC analysis, associative UPLC-MS combined with HPLC, the product of ozone oxidation degradation of dianilino dithiophosphoric acid was analyzed, and the reaction path the inference. The results show that:the intermediate product of dianilino dithiophosphoric acid ozone oxidation of diisobutyl phthalate and tetradecane.