Study on pulsation characteristics of laser-induced cavitation bubble and its degradation of acid black solution

Laser cavitation degradation is a new technology for dye wastewater treatment. By designing and building a laser cavitation experimental platform, the acid black water solution was degraded by laser cavitation under different operating conditions, and the degraded solution was analyzed and characterized by ultraviolet spectropho-tometer to obtain the influence of laser energy and initial concentration of the solution on the degradation ability. The generation process of hydroxyl radical was summarized through the study of laser-induced cavitation bubble pulsation, and the degradation mechanism of acid black was further revealed. The results show that with the increase of laser energy, the degradation rate of acid black solution with initial concentration of 20 mg/L gradually increases from 0.78% to 27.28%. When the laser energy of is 100 mJ, the solution with the initial concentration of acid black in the range of 5-20 mg/L is selected, and the degradation rate decreases from 98.55% to 7.63%. The higher the laser energy is, the greater the degradation rate is. However, if the initial concentration is higher, it is difficult to degrade the acid black solution by laser cavitation.