Investigation Of A New Catalyst For Removing The Kitchen Cooking Oil Fume

Cooking oil fumes, including volatile organic compounds (VOCs) and particulate matter (PM), contain a large number of toxic and hazardous substances, including mutagenic, carcinogenic, teratogenic organic compounds. In China, as some of the restaurants and residential areas intersect, fumes not only seriously affect the health of urban residents, but also cause a wide range of social conflicts, complaints caused by cooking fumes is increasing. In 2000, the Environmental Protection Administration promulgated laws mandating smoke emissions catering units decontamination.Fume purification technologies include physical methods and chemical methods. Physical approach is through the use of cleaning equipment, using absorption, separation, and other physical means of removing smoke pollutants method, commonly used physical methods include mechanical separation, filtration, adsorption, washing, and static electricity. Chemical methods commonly used thermal oxidation and catalytic combustion. Domestic technology and equipment adopt physical methods, which are mostly for the removal of particles matters, without making any chemical treatment, the problem of oil fume pollution isn't fundamentally solved. The technology used in foreign countries is mostly due to consideration of that, legislation requires the particulate matter and volatile organic compounds to be removed at the same time; catalytic combustion can convert the cooking fume to less noxious species, such as oxidation to carbon oxides and water. The research shows that catalytic combustion is the most economical and most direct method of purification. However, at present there is few studies on the catalysts, it's difficult to adapt to the requirements of the situation. In view of this, the purpose of our experiment is to find an efficient and economic catalyst, which can develop into large-scale use of fume purification equipment to meet the needs of the situation.Precious metal catalyst as the active component shows excellent performance, which can remove volatile organic compounds (VOCs) and particulate matter (PM) at the same time. However, due to their high cost and limited resources, the application for the fume purification is obviously unrealistic.A large number of studies have shown that the catalytic activity for organic compounds of rare-earth perovskite catalyst is similar to the activity of the precious metals, even more than precious metal catalysts. China is the most resource-rich countries of rare earth, rare earth reserves and production rank first in the world. Fume purification using rare earth catalyst has good prospects.The essence of the catalytic combustion method is that hydrocarbon is oxidized to carbon dioxide and water, the reaction is exothermic. Ceramic carrier for the fume purifier to warm quickly to working condition would be very beneficial. Therefore, this paper uses ceramic as the carrier of catalyst, La_0.8Sr_0.2MnO₃ active component is deposited on by the immersion method.According to cooking fumes components analysis, the fume contains more than 200 kinds of chemical components, mainly composed of alkanes, alkenes, followed by organic acids, aldehydes, ketones, and polycyclic aromatic hydrocarbons. It is an extremely complex mixture of components, choosing a single gas as the research object, does not have sufficient convincing. Catalyst Characteristics must be integrated into the overall effect of various organic compounds. Because of the complexity of components, the concentration of cooking oil fumes is notoriously difficult to measure. To solve this problem, through a large number of experimental studies, we have set up a scientific, targeted catalytic activity evaluation system. We got a cooking oil fume source which is close to the true state; made a set of oil resistant, high temperature resistant, corrosion resistant, removable and washable catalytic reactor; determined to select CCl4 as the extraction solvent to collect fume samples; determined to use infrared spectrophotometry to measure the concentration of cooking fumes; proposed an accurate and feasible method of calculating conversion rate.Catalyst performance was tested by the catalyst activity evaluation system. The results show that: La_0.8Sr_0.2MnO₃ perovskite catalyst can effectively remove cooking fumes, the cleaning efficiency reached above 80%. In this paper, we also studied catalytic activity under different external factors and got some characteristics and regularity of the experimental method.By XRD and SEM testing the phase of catalyst structure and surface morphology were studied , the results verify the test results of the activity and provided a theoretical basis for the next design of catalyst.Finally, we initially discussed the structure design of the fume purifier using La_0.8Sr_0.2MnO₃ as activity compound.