Study On Degradation Of Pyridine Wastewater By Catalytic Oxidation

Pyridine and its derivatives constitute an important class of compounds and have a wide range of applications in medicine,pesticide production,chemical production,industrial solvents,etc.Because pyridine has high volatility and solubility in water,pyridine wastewater will be produced during the production and application of pyridine and its derivatives.This wastewater is highly concentrated and difficult to biodegrade.Pyridine is classified as one of the biologically refractory compounds,with carcinogenic,teratogenic and mutagenic properties,threatening drinking water safety,ecosystems and human health.Therefore,looking for an efficient and environmentally friendly technology for the treatment of wastewater containing pyridine is crucial to the treatment of industrial wastewater today.This article uses ozone oxidation,ozone catalytic oxidation,ozone assisted catalytic oxidation technology to treat pyridine-containing wastewater.The influence of each operating condition on the degradation rate and COD removal rate of pyridine wastewater was investigated.The operating conditions were optimized through orthogonal experiments,and the treatment effects of several processes were compared to obtain more suitable operating conditions.The reaction kinetics analysis,pyridine degradation pathways and hydrodynamic simulation in the bubble column were also studied.According to the experimental results,the following conclusions are obtained:(1)Ozone oxidation system,the effects of reaction time,wastewater initial pH and other conditions on pyridine degradation rate and COD removal rate were investigated;the results showed that pyridine degradation rate increased with wastewater initial pH(7,8,9,10,11),the reaction time increases,with the initial pH of wastewater(3,4,5)increases almost unchanged;COD concentration with the initial pH of wastewater(3,4,5)increases almost unchanged,with the initial wastewater The pH(7,8,9,10,11)decreases with the increase,and increases first and then decreases with the increase of the reaction time;(2)Ozone catalytic oxidation system,the effects of conditions such as reaction time,initial pH of wastewater,and dosage of catalyst on pyridine degradation rate and COD removal rate were investigated;the results showed that the degradation rate of pyridine increased with the initial pH of wastewater(7,8,9,10,11),the reaction time,the amount of catalyst added increases,with the initial pH of wastewater(3,4,5)increases almost unchanged;COD concentration with the initial pH of wastewater(7,8,9,10,11),the reaction time increases,with the increase of the initial pH of the wastewater(3,4,5)almost unchanged,with the increase of the catalyst dosage(0.25,0.5 g/L)While decreasing,as the amount of catalyst added(1,1.25,1.5 g/L)increases first and then decreases;(3)In the catalytic oxidation system of ozone,the effects of conditions such as reaction time,initial pH of wastewater,dosage of catalyst,dosage of cocatalyst and other factors on pyridine degradation rate and COD removal rate were investigated;the results showed that:pyridine degradation rate With the increase of the initial pH of the wastewater(7,8,9,10,11),reaction time,and the amount of catalyst added,the initial pH(3,4,5)of the wastewater,the amount of co-catalyst The increase is almost unchanged;the COD concentration is almost unchanged with the increase of the initial pH of the wastewater(3,4,5),the amount of co-catalyst added,and the initial pH of the wastewater(7,8,9,10,11),the reaction The increase of time and the dosage of catalyst(1,1.25,1.5 g/L)increase first and then decrease,and decrease with the increase of the dosage of catalyst(0.25,0.5 g/L);(4)Comparing several treatment processes,it can be seen that the additive has the best treatment effect on pyridine wastewater by ozone catalytic oxidation process,and the degradation rate of pyridine is 94.5%.It shows that the addition of co-catalyst is more conducive to the full utilization of the catalyst,thereby improving the degradation rate of pyridine.