Research On The Catalytic Purification And Rapid Detection Method Of Formaldehyde Gas

In recent years,with the enhancement of people's environmental awareness and the increasingly stringent environmental regulations,a variety of indoor purification related products into the market.Especially for catalytic purification.Therefore,this paper mainly uses the current air-conditioning grid,purifier and other components used in the air purification filter non-woven material as a carrier material,the catalytic activity,structure and catalytic mechanism of the Pt catalyst supported on it were investigated.This paper also studies the new simple and rapid and accurate detection of formaldehyde method.We main use the chromogenic agent to react with formaldehyde to achieve rapid detection,and explore the mathematical model of the formaldehyde gas concentration time.For the catalyst of non-woven fabric,two kinds of Pt/PET catalysts were prepared,vacuum adsorption than the conventional impregnation process is simple,the surface of the catalyst prepared with more uniform catalyst etc.The results showed that the best preparation conditions are the concentration of reducing agent(NaBH4)was 0.5mol/L,the loading was 0.8wt%,trying temperature was 80?,trying time was 2h,Formaldehyde degradation rate of 64%.The effects of different initial formaldehyde concentrations(1.71,2.52,7.47mg/m3)on the degradation of formaldehyde were also compared,the formaldehyde degradation rate is high about 68%,finally,Pt/PET passed five test cycles,each time for 24 hours,and still maintain a good activity.The carrier non-woven fabric activated with carbon,prepared by the impregnation method,as the intensity of the carrier is better.The precursor was subjected to reduction using a solution of 80 wt% N2H4·2H2O,and the obtained Pt particles were firmly supported on the surface of the non-woven fabric with activated carbon.When the concentration of N2H4·2H2O solution was 80wt%,the loading of platinum was 0.4wt%,the drying temperature was 80? and the drying time was 2h,the catalytic activity of formaldehyde was the best,it can reaching 73%.The effects of different initial formaldehyde concentrations(7.3mg/m3,2.8mg/m3,1.4mg/m3)on the degradation of formaldehyde were also compared,the formaldehyde degradation rate is high about 77%,finally,Pt/CPETpassed five test cycles,each time for 24 hours,and still maintain a good activity.The rapid detection of formaldehyde gas was maked preliminary study:fuchsin sodium sulfite drip board system: by adding 1.5wt% polyethylene glycol 1000,to sensitivity the color,and produced Hongya sodium sulfate solution with PEG ratio was 1:9,to observe the color and color time more easily and stably.Color time and formaldehyde concentration were discussed by the mathematical model;Phenol reagent Ammonium Ferric Sulfate-drip board system: 1.0wt% polyethylene glycol 1000 as chromogenic agent,and through the study of chromogenic solution dosage,controlling factors of surface active agent to determine the final in the system : 0.4mL +0.4mL surfactant +0.2mL phenol reagent+0.02 mL ammonium ferric sulfate respectively absorb as a chromogenic system.The relationship between the concentration of formaldehyde and the coloration time was established to rapidly determine the concentration of formaldehyde,the two formaldehyde gas concentration rapid detection system,in terms of accuracy and precision to meet the requirements of rapid analysis.