Purification Effect Of Formaldehyde For Compound Purification Processes Of TiO₂ Photocatalysis And Chitosan

Indoor air pollution has not only destroyed people's living and work habitation,but also threatened human health.Nowadays,the development of various new air purification materials and technologies has become a research hotspot,which includes compound purification method.And compound purification method is based on synergistic effect of different purification modes.In this paper,the purification effect of formaldehyde for compound purification processes of TiO₂ photocatalysis and chitosan was studied by combining experimental research with theoretical analysis.This work aims to achieve two effects,one is to optimize the formaldehyde purification effect,and the other is to apply the chitosan materials in the field of air purification.Firstly,TiO₂-polypropylene non-woven fabric was prepared with 4 kinds of TiO₂loading amount.Secondly,26 working conditions were designed.And the purification effects of formaldehyde for TiO₂ photocatalysis,chitosan and compound purification processes were tested.The parameters include TiO₂ loading amount,chitosan weight,initial concentration,relative humidity and purification time.And the purification effect was analyzed by purification efficiency and rate,purification quantity and purification life.Thirdly,to determine whether there was consumption of chitosan materials in the purification process,the Fourier transform infrared spectroscopy?FTIR?of chitosan samples before and after the accelerated test was tested.Finally,the single-pass purification efficiency and resistance of the three purification methods were tested.The results show that:the formaldehyde purification efficiency and purification rate increase with the increase of TiO₂ loading and chitosan weight.Relative humidity has little effect on the photocatalytic purification efficiency.Increasing relative humidity is beneficial to the formaldehyde adsorption by chitosan,and the purification effect of formaldehyde for compound purification processes.The lower the initial concentration leads to the higher the formaldehyde purification efficiency of TiO₂ photocatalysis and chitosan.The compound purification process prolongs the service life of purification material and reduces the consumption of chitosan.The cumulative clean mass of formaldehyde by TiO₂ photocatalysis,chitosan and compound purification process were 1189 mg/m²,647 mg/m² and more than 1900mg/m².The single-pass purification efficiency of compound purification method is the highest,then the TiO₂ photocatalysis.There is no absolute positive correlation between the resistance of three methods and their single-pass purification efficiency.