Research On The Identification And Control Of Pollutants Released From Wood-based Panel

People spend an average of 87% of our time indoors on the dairy day,including in a residence and office-factory,so that the indoor air quality is very important for us.However,the indoor air quality is bad because of the inadequate ventilation and a variety of indoor pollution sources.The wild use of the wood-based panels was the major factor for indoor chemical pollution.In this study,particalboard,one common type of wood-based panels,was used to investigate the released pullutants,including types and contrubition to odor.The effect of heat-treating on the pollutants was studied and the high efficiency catalyst was prepared for formaldehyde removal.The resuls were as follows.The compounds and corresponding concentration released from particleboard at23 ?,35 ? and 50 ? were investigated.The pollutants were composed of formaldehyde,alkane,aromatics,aldehydes?excluding formaldehyde?and other substances.When the loading factor was 19.6 m2/m3,the concentrations of formaldehyde and TVOC were 0.5 mg/m3 and 0.62 mg/m3 under 23 ? in an air-tight environment chamber.Temperature could influence the emission of pollutants in type numbers and concentration,as well as the percentage of every substance.The concentration of formaldehyde under 50 ? was 6.92 times high than that under 23 ? and the concentration of TVOC under 50 ? was 3.98 times high than that under 23 ?.The raise of valeraldehyde and caproaldehyde after the lifting of temperature were the most obvious among the VOCs.The concentrations of valeraldehyde and caproaldehyde were47.80 ?g/m3 under 23 ? and 1565.47 ?g/m3 under 50 ?,meanwhile,the percentage was lifted to 66% from 8%.With the increase of air change per hour?ACH?,not only the concentrations of VOCs but also the number of VOCs numbers declined.Valeraldehyde and caproaldehyde were the major odor sources of the particleboard with a contribution of 90%.This was caused by their pretty low odor thresholds compared with other compounds.HCHO was not responsible for the odor with a contrition of 2%.The changes of released pollutans from wood-based panels and the odor intensity were studied after the heated-treated process The condition of the heat-treating processwere 50 ? and 60 ? with 6h or 12 h.The concentrations of HCHO and TVOC would decline after the heat-treated process of particleboard,as well as the odor intensity.After the heat-treating of 60 ?-12 h,formaldehyde,TVOC and odor intensity of the tested particalboard reduced 51.2%,44.4% and 91%,respectively.Heat-treatment was an effective method to accelerate the pollutants emission.Formaldehyde was the major pollutant from particleboard.In order to improve the catalytic activity of Ag/MnOx catalyst for formaldehyde oxidation at room temperature,modi?cation of MnOx by Fe doping was carried out.The HCHO mineralization ratio at ambient temperature of Ag/Fe0.1-MnOx can reach 100% with an initial HCHO concentration of 230 ppm.With the support of characterization results,the reaction mechanism was figured out.The higher catalytic activity of Ag/Fe-MnOx was resulted from the synergistic effect between Ag,Fe and MnOx nanostructure,which promoted higher amount of surface adsorbed oxygen as well as easier activation of O₂.