Research On Foam-type Acoustic Catalysts

Organic pollutants are quite common environmental pollutants.With an extensive environmental sources,organic pollutants may be produced by dyeing wastewater,sewage irrigation,pesticides,domestic garbage,medical waste and so on.Most of the organic pollutants are not easily degraded by ecosystem,consequentially not only posing teratogenic,mutagenic,carcinogenic and other high-risk threats on humans,animals and plants,but also bringing serious damages to ecosystem.Ultrasonic irradiation can degrade some organic pollutants that are hard for biodegradation.As the safe and clean ultrasonic waves enjoy high penetration depth in water and soil,its irradiation makes it possible to separate pollutants from the environment and to generate strong oxidizing free radicals in water bodies and mud,in the process of degradation.However,the absorption rate of ultrasonic waves in water bodies is very low and a lot of energy would be consumed for ultrasonic cavitation.How to reduce the energy consumption in the ultrasonic degradation process and improve the utilization rate of ultrasonic waves is what many researchers have been dedicated to.In addition,the integrated utilization of ultrasonic degradation technology and other complementary technologies has become one of the hot spots in organic pollutant treatment research.Before the study of the catalytic performance of the foam material,the degradation of methyl orange was used by ultrasonic alone,and the power and the frequency were used respectively.We achieved when the power at 300 W and with the mix frequency the ultrasonic degradation of methyl orange was the best.In the study of nickel foam as a catalyst,the use of nickel foam alone to degrade methyl orange solution has little effect.When using foam nickel synergistic ultrasound on methyl orange solution,its degradation rate increased.Then,the degradation rate of nickel foam reached 90% after synergistic ultrasonic and magnetic fields were applied to methyl orange solution for18 H,and almost completely degraded.In the study of aluminum foam as a catalyst,the use of foam aluminum alone in the methyl orange solution has almost no effect.When aluminum foam synergistic ultrasound was used to treat methyl orange solution,its degradation effect was greatly improved,and its degradation rate reached 83.13% after 8H.When foam aluminum cooperates with ultrasonic and magnetic field to act on methyl orange solution for 8H,its degradation rate can reach 90%.Finally,after foamed aluminum synergistic ultrasound and current action with methyl orange solution 6H,its degradation rate can reach 98.70%,the most significant effect.The results show that when aluminum foam or nickel foam alone degrades the methyl orange solution,the degradation rate is small because the protection of the surface passivation layer cause the materials cannot fully participate in the reaction.Under the ultrasound synergetic the foam material,the foam material and the ultrasonic synergistic magnetic field and current,which can greatly increase the degradation rate of methyl orange.Because under the synergistic effect,the utilization rate of the foam material can be improved,and the cavitation effect can also be improved which can generate more free radicals,redox,etc to degrade methyl orange.