Research On Release Behavior Of Formaldehyde And Volatile Organic Compounds From Wood And Its Products

In order to have a better understanding of the release behavior of formaldehyde and volatile organic compounds(VOCs)from wood and its products,this paper takes Cathy poplar and Southern yellow pine as the research object and treated with heat treatment and benzene-ethanol extraction respectively.The changes of formaldehyde content before and after treatment were measured by perforator extration method,and the changes of main VOCs components and its contents in wood before and after treatment were analyzed by Gas Chromatography-Mass Spectrometry(GC-MS).The following conclusions were obtained:1)Microamounts of formaldehyde were found in neat Cathy poplar and Southern yellow pine and formaldehyde content was 140 ug/100 g and 175 ug/100 g respectively,and the formaldehyde content increases with the increase of heat treatment temperature.When the heat treatment temperature was 140 ℃,the formaldehyde content in Cathy poplar and Southern Yellow Pine changed to 192 ug/100 g and 267 ug/100 g respectively,When the heat treatment temperature increased to 220 ℃,the formaldehyde content in Cathy poplar and Southern yellow pine increased to 289 ug/100 g and 363 ug/100 g.Compared with neat Cathy poplar and Southern Yellow Pine,the formaldehyde content of Cathy poplar and Southern yellow pine treated with benzene-ethanol extraction decreased to 124 ug/100 g and 147 ug/100 g respectively.2)There are 126 kinds of VOCs in neat Cathy poplar,the species of VOCs decreased to104 species after heat treatment at 140 ℃,and increased to 181 species after heat treatment at220 ℃.Compared with the species of VOCs in neat Cathy poplar,119 kinds of volatile organic compounds in Cathy poplar after benzene-ethanol extraction,and the main VOCs in Cathy poplar include alcohols,acids,aldehydes,alkenes,alkanes,ketones and furans.3)There are 86 kinds of VOCs in neat Southern Yellow Pine,the species of VOCs increased to 93 species and 131 species after heat treatment at 140℃ and 220℃ respectively.Compared with the species of VOCs in neat Southern Yellow Pine,the species of VOCs inSouthern yellow pine increased to 131 after benzene/alcohol extraction treatment.Those VOCs include alcohols,aromatics,acids,aldehydes,alkenes,alkanes,furans,ketones and esters.4)Heat treatment and benzene-alcohol extraction can effectively reduce the contents of alkenes,alcohols and acids in neat Cathy poplar and neat Southern yellow pine,especially the alkenes were almost completely removed from the neat Cathy poplar and neat Southern yellow pine after benzene-alcohol extraction.In the meanwhile,heat treatment and benzene-alcohol extraction could increase the content of alkanes in Cathy poplar and Southern yellow pine.In addition,heat treatment can also increase the content of aldehydes in wood.5)Both high temperature heat treatment and benzene-alcohol extraction can reduce the content of main volatile organic compounds in wood.High temperature heat treatment will lead to the decomposition of some components in wood,while benzene-alcohol extraction would bring some new substances to Cathy poplar and Southern yellow pine.