Effect And Mechanism Of Degradation Of Carbamazepine In Piezo-Fenton Process Based On Barium Titanate

Carbamazepine?CBZ?is a pharmaceutical organic pollutant widely present in environmental waters.Although its concentration is low,its biological toxicity is bound to constitute aquatic organisms and human health in the environment.Potential threat;the Piezo-Fenton process is an emerging advanced oxidation technology in the field of water treatment.Therefore,this paper explores the effect and reaction mechanism of CBZ degradation in water by Piezo-Fenton process.First,a self-made Ti?OH?₄ powder was used as the titanium source,and Ba?OH?₂?8H₂O was used as the barium source.A high-purity tetragonal BT powder was synthesized by hydrothermal method.The reaction temperature and reaction time were investigated.The effect of the preparation of BT powder was200?and 68 h.The samples were characterized by scanning electron microscope?SEM?and X-ray diffraction?XRD?.It is verified that the growth process of BT powder conforms to the dissolution-precipitation mechanism.The degradation effect of each process on CBZ was explored,and the feasibility of the scheme was verified.The results show that the Piezo-Fenton process has excellent degradation effect on CBZ.The final degradation rate is as high as 99%,and the degradation process conforms to the quasi-first-order reaction kinetic model.The US/Fe???process and the piezoelectric catalytic process are calculated.The synergy coefficient?=2.1,showing a significant synergy.The effects of ultrasonic frequency,initial pH value of solution,Fe???concentration,and BT dosing volume of Piezo-Fenton process on the degradation efficiency and reaction kinetics of CBZ in water were investigated.The results show that only low-frequency ultrasound?45 kHz?Can drive the process to degrade CBZ.The acidic environment?pH=3?is more conducive to the reaction.The optimal concentration of Fe???is 10 mg?L^-1,and the optimal dosage of BT is 2 g?L^-1.The reaction mechanism of the Piezo-Fenton process to degrade CBZ in water was investigated.By measuring the change of H₂O₂ concentration in the piezoelectric catalytic process,it was found that the process would rapidly generate a large amount of H₂O₂,and it accumulated in the solution and was not consumed.It provides a good theoretical basis for the subsequent addition of Fe???to form a Piezo-Fenton process.Through free radical capture experiments,the existence of various active substances such as e^-,h⁺,H₂O₂,?OH,and?O₂^-were determined.Based on subsequent calculations of the first-order reaction kinetic constant(k_obs)inhibition rate,their initial inferences were deduced.The reaction mechanism,that is,?OH is the only free radical that can directly degrade CBZ.There are two generation paths.One is directly generated by the Fenton reaction between H₂O₂ and Fe???in the solution.A series of reactions were first converted to H₂O₂,and then produced by the Fenton reaction with Fe???.Path two was first proposed in this study.In order to verify the above inference,biological enzyme inhibition experiments were supplemented,and the results showed that H₂O₂ in the solution was decomposed by catalase?CAT?and?O₂^-in the solution was consumed by superoxide dismutase?SOD?.Rate,indicating that the above inferences are basically correct.In summary,the work done in this research has important reference significance for the preparation of high-purity tetragonal BT powder,the influencing factors and reaction mechanism of CBZ degradation in water by the Piezo-Fenton process,and illustrates the removal of this process.CBZ in water has good feasibility.