Research Of Exfoliated Graphite Combined With Ultrasound Irradiation Dealing With Industrial Wastewater

The thesis introduces treating method and present situation on domestic and overseapharmaceutical intermediates industrial waste water, and it also reviews the structure andpurpose of expanded graphite （EG）, and it also looks back the development of EG preparedby natural flake graphite as raw materials. At the same time, the thesis also introduces theapplication of EG in dealing with industrial waste water in recent years. After the comparativeanalysis, it has been discovered that EG has a strong and adsorptive capability and ultrasoundirradiation has a strong degradation capability, but all of them just plays a single role in theprocess of treating water pollution. Thereby, it is necessary to create a combination method ofthe adsorption capability of EG and the strong degradation capability of ultrasound irradiationto treat the industrial waste water.In the thesis, EG is prepared by chemical oxidation method which has completeindependent intellectual property in our laboratory. Meanwhile, the structure and morphologyof EG are also characterized by SEM. Then, EG is used as raw material to deal with theindustrial waste water with the combination method of EG and ultrasound irradiation.In the process of the research, we treated three types of industrial waste water （3p motherliquor,3p sulfonated waste water, regenerated waste water） which was from Chem China ofHebei fuheng company. By varying the time of ultrasound irradiation, the dosage of EG, theadsorption time of EG, the dosage of H₂O₂and the oxidation time of H₂O₂, we treated threetypes of industrial waste water. At the same time, we used ultraviolet spectrophotometry andthe potassium dichromate titration method to determine the treatment results. The experimentresults had indicated that the different treatments had the different effects when the sameindustrial waste water was treated. The previous influence factors were decided the differentremoval rate and COD. The experiment results had also proved that the combination methodof H₂O₂, EG and ultrasound irradiation on treating the three kinds of industrial waste waterhad the best result. Meanwhile, we also obtained the optimum condition in the combinationmethod of H₂O₂, EG and ultrasound irradiation on treating the three kinds of industrial wastewater. Otherwise, it was proved well by the experiment that the combination method of EG andultrasound irradiation on treating the industrial waste water had better capability in theprocess of dealing with the industrial waste water. The combination method of EG andultrasound irradiation is also a new method to treat the industrial waste water. In the lastchapter, we had discussed the mechanism on the combination method of EG and ultrasoundirradiation. We aslo obtained some significative conclusions.Main works in this thesis:⑴EG with250mL/g volume expansion is prepared by50mesh of flake graphite as rawmaterials using chemical oxidation method, which has complete independent intellectualproperty.⑵The structure, the morphology and the relevant information of EG have beenmeasured by SEM.⑶We use the methods of ultraviolet spectrophotometry and potassium dichromatetitration to record the absorbance and titration volume, which are measured in differenttreatments of every industrial wastewater and compute removal rate and COD, and draw thepictures of removal rate and COD.⑷We treat three types of industrial wastewater which is from Chem China of Hebeifuheng company by the combination method of EG, H₂O₂and ultrasound irradiation. TheCOD of the three types of industrial waste water is greatly reduced and the removal rate of thethree types of industrial waste water is higher. The COD of3p mother liquor is from8880mg/L to3360mg/L, and the removal rate of3p mother liquor is up to62.16%. The CODof3p sulfonated waste water is from18240mg/L to12160mg/L, and the removal rate of3psulfonated waste water is up to33.33%. The COD of regenerated waste water is from12800mg/L to6080mg/L, and the removal rate of regenerated waste water is up to52.50%.⑸We have discussed the mechanism on the combination method of EG and ultrasoundirradiation in treating industrial wastewater, the mechanism of ultrasound irradiationdegradation, the adsorption of EG and H₂O₂Oxidative decomposition, the mechanism of thecooperative treatment.