Study On The Design Of In-car Oxidation Catalytic Purifier For Formaldehyde-removing

With the rapid development of economy and society, cars become popular. The time that people stay in cars is increasing, thus the incidents caused by in-car air pollution occur frequently. In-car formaldehyde is a common and harmful pollutant with long release cycle, and current in-car purification device are always ineffective in removing formaldehyde, so developing a safety and environmentally friendly is imperative. The catalytic oxidation technology is effective in purifying formaldehyde, and could change formaldehyde into harmless carbon dioxide and water at room temperature. Therefore, developing in-car purifier based on catalytic oxidation technology has a good prospect.The mainly contents of this thesis was that:doing surveys on in-car formaldehyde pollution in large auto store in the city of Chongqing; developing and characterizing efficient formaldehyde oxidation catalyst; Designing structural parameters of in-car oxidation catalytic purifier and analyzing the factors that affect the performance of the purifier; comparing the effects of in-car oxidation catalytic purifier and other purifiers based on other technologies.The survey results showed that only58cars reached the standard out of91and the overall unattainment rate is36.26%. In new cars, the minimum formaldehyde concentration is0.01mg/m", the maximum is0.60mg/m3, and the average is0.10mg/m3.65.59%of new cars meet the in-car formaldehyde concentration national standard ("passenger car within the Air Quality Assessment Guide" GB/T27630-2011),22.58%was1time more than the national standard, and4.3%was2times more than the national standard and the highest in-car formaldehyde concentration exceeded the national standard by5times. CexZryMn1-x-yO2(x, y=0.1～0.9) and La modified Y-A12O3were prepared with co-precipitation method, and then these two materials were mechanical mixed with a certain percentage. After dipping with0.7%Pt, this mixture was dried, calcined, and coated in cordierite honeycomb supporter. At last drying and calcining the mixture once more. Characterizing of the catalyst were conducted by BET, H2-TPR and XRD.Monolithic honeycomb catalyst was the core component of this in-car purifier, and fittings included a filtering system made from HEPA and activated carbon network gale, low noise centrifugal fan and white metal shell. Five influencing factors were investigated in this thesis, that is different entering air methods, the addition of activated carbon filter, different initial concentration of formaldehyde, and the size of the oxidation catalyst. After the optimization of parameters, this in-car purifier could degrade87.93%of the formaldehyde in one hour.The result of the comparison between this in-car oxidation catalytic purifier and other purifiers based on other technologies showed that this in-car oxidation catalytic purifier had high efficiency.