The Study On Ultrasonic Catalytic Treatment By Cu-Co Catalyst In Petrol Wastewater Treatment

Oil is a vital resource for the development of a country under the high competition of energy.In recent years,enhanced oil recovery?EOR?is widely used in China to improve the recovery rate of oil fields in the petroleum industry,resulting plenty of high viscosity wastewater containing a large amount of polyacrylamide?PAM?and creating a lot of serious environmental problems.The purpose of this project is to explore an efficient,fast and clean method to treat the thrice oilfield sewage and remove the viscosity of the wastewater to meet the wastewater reuse standards of enterprise.This paper focused on the treatment of the thrice oilfield sewage of the Daqing Petroleum Company and building a new type treatment process for thrice oilfield sewage.And this project investigated using ultrasonic catalytic treatment by Cu-Co composite catalyst.The research target of this paper is Polyacrylamide wastewater and the thrice oilfield sewage provided by Daqing Petroleum Company,and to find out the optimal parameters of the experiments.At the same time,the dynamics and mechanism of the reaction are discussed briefly in this paper for t he future research.Firstly,the Cu-Co composite catalyst was prepared by chemical co-precipitation method,then the preferred conditions for the preparation of the catalyst was as follows: The concentration of n?Cu?/n?Co?was 1: 1 and the concentration of precipitant Na OH was 3mol / L.The Cu-Co composite catalyst were measured through BET?XPS?SEM and so on which proved that the specific surface area of the catalyst was116.463 m2/g and the average pore size was 3.399 nm.The prepared particles were homogeneous and belong to the nanometer catalyst,and have good catalytic performance.The Polyacrylamide wastewater was treated by ultrasonic catalytic treatment with Cu-Co catalyst.The optimum reaction conditions were determined by single factor experiment analysis.The optimum reaction conditions were as follows: temperature was at room temperature;reaction time was 30 min;ultrasonic power was 300W;catalyst dosage was 0.20 g;the concentration of H₂O₂ was 8 mmol/L.PAM wastewater viscosity removal rate could reach 88.7% which meet the enterprise standards.And the oxidative capacity and the production of hydroxyl radicals between the different oxidative systems were compared in this paper,the experiments results showed that there were a large amount of hydroxyl radicals and the heterogeneous Fenton system is formed in the US/H₂O₂/CAT oxidative system which lead to a stronger oxidizing ability.UPLC were implemented to discuss the the degradation reaction of polyacrylamide.It verified Polyacrylamide was oxidized and brought about new matter in the system.It can be inferred that Polyacrylamide had a chain-breaking reaction and the oxidation products of polyacrylamide were oligomers of polyacrylamide and acrylic acid.Finally,the actual thrice oilfield sewage provided by Daqing Petroleum Company was treated by ultrasonic catalytic treatment with Cu-Co catalyst.The results indicated that this process for the removal of the actual wastewater's viscosity also had a satisfied effect.The change of polyacrylamide before and after the reaction was confirmed by infrared absorption spectroscopy.This verified the the occurrence of chain reaction of polyacrylamide in the system.Meanwhile,the GC-MS was applied to analyze the actual wastewater samples before and after treatment,it was found that the old peaks disappeared and new peaks were formed after the reaction in the reaction system which indicating that the organic matters were degraded and new substances were formed verifying the strong oxidation capacity of the reaction system.