Effect Of Thermal Treatment Conditions On VOC Emission From Moso Bamboo

In order to provide theoretical reference for reduction and utilization of VOC emission from bamboo flooring during thermal treatment.,moso bamboo(Phyllostachys pubescens)was used as experimental material in this study,mathematical function was obtained by analyzing the relationship among VOC release,temperature and time.The thermal decomposition mechanism were obtained basing on the analysis of pyrolysis process of bamboo at different heating rates.The effect of thermal treatment on the release of VOC components was gained by gas chromatography-mass spectrometry.The relationship between VOC and chemical composition was explored by infrared spectrum,gas chromatography-mass spectrometry and chemical composition analysis.The main conclusions are as follows:Temperature and time both affected the release of VOC from bamboo.In the range of temperature and time from 150 to 210? and 1 to 3h,the higher treated temperature,the longer treated time,VOC release from bamboo were more.According to Table Curve 3D software,the mathematical model of VOC emissions,treated temperature and treated time of moso bamboo was established.The temperature range of the main pyrolysis stage of bamboo were 160? to 390?,and weight loss rate reached 70%at this stage.When the heating rate was 5?/min,the activation energy in thermal decomposition stage was between 2 and 4.5kJ/mol.At the heating rate of 10,20,30?/min,the activation energy of the high temperature stage was between 4 and 25kJ/mol.The activation energy in high temperature stage were higher than that of the low temperature stage.Release of VOC from bamboo were mainly composed of ketones,acids,aldehydes,alkanes,aromatic hydrocarbons and terpenes during thermal treatment,and heated temperature had little effect on species of VOC.Relative proportion of ketones,acids,aldehydes and alcohols compounds accounted for 9?17%,The relative proportion of alkanes,aromatic hydrocarbons and terpenes compounds were about 5?24%,14?22%and 26?52%,respectively.The treatment temperature had obvious influence on the content of alkanes,aromatics and terpenes compounds.With the increase of temperature,the relative content of three kinds of compounds increased.The treatment time had no obvious influence on the content of alkane and aromatic hydrocarbon.The content of terpenes compounds decreased with treated time increasing.The main component from the VOC were a-cedrene,a-copaene,tetradecane,pentadecane,cymene,xylene,cyclohexanol,nonanal and decanal and benzaldehyde.During thermal treatment,cellulose and hemicellulose were both decomposed,lignin was degraded a little,a few of original extracts disappeared,new extracts were formed with degradation of the three main substances.O-xylene,vanillin,acetophenone,coniferyl aldehyde,a variety of phenolic compounds of VOC were degraded from the three major substances,of which coniferyl alcohol,benzaldehyde and guaiacol and other substances came from the extracts.At the same treatment temperature,the acidity of bamboo was strengthed with time increasing.When the treatment temperature was 180?,the acidity of bamboo was highest at the same treatment time.