Study On The Degradation Of Carbamazepine And Humic Acid In Water Using Ultrasonic Combined With Persulfate Method

With the rapid development of the global economy, content of production and living waste discharge into the environment increased year by year, more and more type also the amount of organic pollutants is detected in water, there has been a serious threat to human health of these substances. Persistent organic substances carbamazepine and humic acid were investigated using ultrasound combined persulfate methods and the mechanism of their degradation also studied. A novel kinetic model was established to describe the humic acid mineralization process in sono-activated persulfate system.Through degradation of carbamazepine(CBZ) using ultrasound combined with persulfate methods, the affection of the persulfate dosage, ultrasonic power, the solution p H, reaction temperature and substrate concentration and other factors were discussed. The results showed that:(1) there are synergistic effect alone ultrasound and persulfate systems;(2) removal rate of CBZ was increased when dosage of presulfate increasing;(3) the effect of ultrasonic power degradation have a certain influence;(4) species of radicals and CBZ distribution were different when solution p H change, CBZ removal rate at different p H values is p H5> p H3> p H9> p H11;(5) degradation of CBZ need high energy in ultrasound- persulfate systems, the apparent activation energy is 119.4KJ / mol. When below 30 ?, the reaction cannot proceed smoothly;(6) CBZ concentration increases leading to reduced removal rate at the end of the reaction, but the total removal amount of substrate increase.Ultrasound degradation of humic acid(HA) has been investigated in the presence of persulfate anions at ultrasonic frequency of 40 k Hz. The effects of persulfate anion concentration, ultrasonic power input, HA concentration, reaction time, solution p H and temperature on HA removal efficiency were studied. It is found that:(1) under the conditions that dosage of persulfate is 100 m M, ultrasonic power input is 200 W, solution p H value is 3.0, the reaction temperature is 50 ?, up to 90% HA removal efficiency was achieved after 2 hours reaction while the initial concentration of HA is 30mg/L;(2) In this system, sulfate radicals(SO4-?) were considered to be the mainly oxidant to mineralize HA while persulfate anion can hardly react with HA directly;(3) A novel kinetic model based on sulfate radicals(SO4-?) oxidation was established to describe the HA mineralization process mathematically and chemically in sono-activated persulfate system. According to the new model, ultrasound power, persulfate dosage, solution p H and reaction temperature have great influence on HA degradation;(4) Different initial concentration of persulfate anions and HA, ultrasonic power, initial p H and reaction temperature have been discussed to valid the effectiveness of the model, and the simulated data showed new model had good agreement with the experiments data.