Degradation Of Organic Pharmaceuticals By Rare Metal Plating On Titanium Electrode Coupled With Ozone

Pharmacruticals and personal care products(PPCPs),which is being extensive used as environment pollutants with potential physiological effects in recent, has attracts widespread attention from the scientific community and socienty. PPCPs in the environment have two main sources, as they cannot be effectively removed in the processing of a sewage treatment plant, the other is a human or animal husbandry agricultural activities.Its concentration in the water environment is only the nanogram level to microgram level, but the potential threat to human and even the ecosystem as a whole is difficult to ignore.Long exposure under its pollution, may cause the secretion of human body and the female reproductive system disorders and aquatic organisms, and many other problems.Most of the PPCPs refractory, strong polarity, soluble and the characteristics of the weak volatile in water, make them difficult to evaporate globally like traditional persistent organic pollutants(POPs), which means that the PPCPs in the environment spread by water and food chain.Therefore, to develop a new and conventional process which is mutual cooperational and economic PPCPs treatment has become an urgent need to water treatment field.Metal electrode electrocatalytic oxidation technology and ozone oxidation process is environmentally friendly oxidation technology, so they attracts the focus of environmental researchers to study organic drug treatment.However, due to the limitation of ozone oxidation and electrolysis potential window, they both share the shortcomings of a low efficiency and, removal uncompletely. Based on the above, in order to establish a highly effective degradation efficiency of oxidation system, this paper studies the oxidation efficiency under the coupling and the optimum working condition of the electrode with the titanium plating metals.Rare metal plating on titanium electrode was used in the electrocatalytic-ozone oxidation coupling system to study the degradation efficiency of carbamazepine in the first. The results showed that the electrode has obvious synergistic effect in the oxidation react coupling system.For example, 8 minutes under the same experimental condition,the react had a carbamazepine removal rate about 46.91% under the optimal conditions, which is 15.07% larger than single ozonation plus single electrolysis only. The removal rates of the system using other electrode is larger than those single ozone and single electrode systems and the value increased respectively 8.18%(titanium ruthenium plating iridium), 10.80%(titanium ruthenium plating titanium), 10.81%(titanium plating iridium tantalum), 2.04%(titanium ruthenium plating iridium tin). In addition, the results of degradation of Diclofenac sodium by electrolysis-ozonation also showed high degradation efficiencies. For example, 16 minutes under the same experimental condition,the electrolysis-ozonation had a diclofenac sodium removal rate of 97.26% under the optimal conditions, which is 49.99% larger than single electrolysis plus single ozonation only. The removal rates of electrolysis-ozonation system using other titanium base rare metal electrode for diclofenac sodium is larger than those single ozone and single electrode systems and the value increased respectively 29.86%(ruthenium plating iridium), 46.12%(titanium ruthenium iridium tin plating), 23.04%(titanium titanium plating platinum plating), 5.68%(titanium ruthenium plating titanium). indicating that the oxidative system had a good prospect for application in water treatment.The influence factors of the oxidation coupling system has been studied, the result shows that the ozone concentration, current intensity and magnetic force agitator rotational speed, p H value, initial concentration, free radical scavenger, type of electrolyte has influence on the system.Under existing conditions, in the response surface experiment, initial solution p H, ozone concentration and the current strength these three affect factors of degradation rate of carbamazepine and diclofenac sodium in electrolysis-ozonation system using platinum coated titanium electrode is not a simple linear relationship, but its two-two shares some degree of interaction, and effect of carbamazepine on the degradation rate of the ozone concentration is the most significant, followed by the current strength and the initial p H of the solution. The optimum conditions obtained from response surface experiment when the current is 0.15 A, the ozone concentration is 0.4mg/L, and the p H value is 7.3.When processing 8min under the experimental conditions,the carbamazepine degradation rate can reach 94.71%. The experiments prove that the actual value and the predicted values fit well(no more than 5%), and the deviation is 2.19%. In addition, When processing 3min under the experimental conditions,the diclofenac sodium degradation rate can reach 89.28%. The experiments prove that the actual value and the predicted values fit well(no more than 5%), and the deviation is 2.98%.