| Bamboo Scrimber,a new type of decoration material which is developing rapidly inrecent years,releases free phenol and other VOC, aldehyde molecules doing harm to theenvironment because of the using of Phenolic Resin adhesive（PF）in its process of productionand processing.However,the harm brought by the free phenol and other VOC, aldehydemolecules has not been drawn a great attention by people including the producers and theconsumers.There has been a set of comparatively systematic testing methods and standardsaiming at testing phenolic substance in the water and air domestic and overseas while the thestudy of VOCs in the wood was limited and lacked.The paper,in which the bamboo scrimber board is chosen as the research object, is a astudy on the rule of the free phenol，VOC and aldehyde material to release,the amount of theirreleasing and the detecting method.In the research,it is mainly focused that how the varyingtemperature, loading rate and the times of air in the small-scale environmental chamber affectthe amount of the harmful substance’s releasing.Also,The feasibility of threemethods(small-scale environmental chamber,via steam distillation or cooking,ultrasonicextraction method) to collect free phenol was studied and compared.The experimental results showed as follows：1. The small-scale environmental chamber method was adopted and the emission rate ofharmful volatiles in the early was larger,with the extension of time, the content to release wasreducing gradually,it reaches a dynamic equilibrium in10to13days or so. The emission ofharmful substances was mainly free phenol,the second was the TVOC and aldehydematerial.When the temperature of small-scale environmental chamber was28℃,relativehumidity of50%,loading rate for2:1, air changes rate for0.5times per hour, the content of freephenol accounted for45.3%,VOC accounted for34.5%, aldehyde materials accounting for20.3%of the total amount of volatile substances in material A. 2. The conditions of temperature, loading rate and air changes of influenced on emissionof phenol significantly in material A. As temperatures rised, the harmful volatile substancesrelease to increase gradually.When temperature was23℃,28℃and35℃,the content of freephenol were356.3μg·m-3,463μg·m-3,612.2μg·m-3respectively.With the increase of loadingrate,the harmful volatile substances increased.Along with the increase of air changes,it wasgood to reduce harmful volatile matter to release.Air changes was0.5time per hour，1.0timeper hour and1.5time per hour,the content of free phenol to release was260.1μg·m-3，105.7μg·m-3and55.7μg·m-3respectively.3. The bamboo scrimber in non-treated released other VOCs that were mainly toluene,styrene, o-xylene, and the maximum content to release was31.30μg·m-3、58.37μg·m-3、39.99μg·m-3respectively，and the maximum content of TVOC was352.44μg·m-3.The bambooscrimber by surface finishing wood oil materials mainly released benzene, toluene, butylacetate, ethyl benzene, styrene and o-xylene,and so no.The maximum content was4.93μg·m-3、61.44μg·m-3、13.64μg·m-3、10.91μg·m-3、65.59μg·m-3respectively，and the content of TVOCwas361.11μg·m-3.The material about aldehydes in bamboo scrimber released mainlyformaldehyde,acetaldehyde, acrolein/acetone.The plate by surface treatment releaseed less thansurface non-treated plate. In fact,wood wax oil can hinder the harmful volatile substancesreleasing from the plate but increase content of VOC. The bamboo scrimber increased with theincrease of gel content.4. The method of ultrasonic extraction-gas chromatography is established to determinatefree phenol content in phenolic glue diping materials such as particieboard, phenolic fiberboard，and so on.The method used ultrasonic extraction device,with acetone as solvent toextract material of free phenol,octyl alcohol as internal standard, and use GC-FID toanalyze.The experimental results showed that this method of standard addition recovery was84.1%-104.1%,relative standard deviation less than5%,the precision is good.The liner rangewas0-0.32mg·m-3,the correlation coefficient R2=0.9996,and it satisfies the requirement oflinear correlation. 5. The method of steam distillation was studied (75℃,85℃) to collect free phenol frombamboo scrimber material.The results of the experiment showed that the distillation efficiencywas lower and the time to collecting sampling longer.So it was preliminarily considered thatthe method was unsuitable for the free phenol in bamboo scrimber board.At the same time，thecooking method (95℃) was studied，results showed that massive phenol was still not collectedafter10hours.So this approach is considered unfeasible to collect free phenol from bambooscrimber board.6. The results of papers provided a basic and feasibility data for the establishment nationalstandard of "Determination of phenol emission from wooden materials and their furnishingproducts—Small chamber method". |
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