Studies For The Ultrasonic Cavitation Field Distribution Measurement Method And Its Influence On Oxidative Desulfurization

In recent years, with the world’s increasing strict environmental regulations, fueloil depth desulfurization has become a worldwide important topic. Oxidativedesulfurization (ODS) has become the research focus because of its mild reactionconditions and simple operation process. But the long reaction time leads tounnecessary lost of reagent which makes the cost rise. The application of ultrasoundcan significantly improve this situation. Ultrasonic cavitation intensity and itsdistribution affect the chemical reaction rate and chemoselectivity since the ultrasoniccavitation is the driving force of sonochemical reactions. Effective region informationcan be got by measuring the cavitation field. The common technique to determinespatial sound pressure fields is to scan the sound field pointwise which istime-consuming and expensive and thus limits its application in the industry. In thiswork, aluminum foil erosion method was used to measure the distribution of theultrasonic cavitation field which is easy cheap and simple operation. MATLABsoftware is used to analyze the aluminum foil erosion image and achieve the goal ofquantitative measurement. The three-dimension visualization of the ultrasoniccavitation field can be realized at the same time. Analyzed the results by slicing thereconstructed field in several positions, the spatial distribution regularities of thesingle transducer ultrasonic cavitation field can be derived and the reliability of thereconstructed field can be verified in the mean time.According to the theory of sonochemisty, particles in the ultrasound field canpromote the effect of the ultrasonic cavitation. In this work, powder active carbon,granule active carbon and alumina was added into the ultrasound field to enhance theODS efficiency and lower the cost. In light of the properties of the oxidativedesulfurization system, the distribution of cavitation field in liquid-solid two-phaseand liquid-liquid-solid three-phase system was measured to obtain the influence ofparticle adding in the ultrasonic cavitation field and find out suitable solid catalyst tooptimize the process of ODS. The data can also help to investigate the mechanism ofODS.