利用光聲法偵測木質材料揮發性有機物逸散之研究—以甲醛為例

The Detection of Volatile Organic Compounds (VOCs) Emissions in Wood Based Materials by Using Photoacoustic-A Case Study of Formaldehyde

龍暐(Way Long) ； 藍浩繁(Haw Farn Lan) ； 黃耀富(Yaw-Fuh Huang)

《林產工業》 26卷1期 (2007/03) Pp. 1-13

https://doi.org/10.6561/FPI.2007.26(1).1

摘要

木材為多孔性材料其具有調溫、溼之功能，因此木質材料廣被使用在室內建築建材，然而木質材料加工所使用之揮發性有機物（volatile organic compounds）在施工後之逸散，已成為室內空氣品質的重要課題。本研究試以光聲法（photoacoustic） 使用雷射激光源（optical parametricoscillation-OPO），量測頻率範圍2796.0 cm^(-1)～ 2806.0 cm^(-1)，在一般常壓環境下（1 atm、溫度25℃+2℃ 、相對溼度60%+ 5%），採用開放式光聲感測器，以玻璃乾燥皿來控制環境影響，並利用高解析分子吸收光譜資料庫（high-resolution transmission molecular absorption database-HITRAN）光譜資料庫加以比對分析揮發性有機物的種類-以甲醛為例之定性、定量分析，甲醛之光聲特徵頻譜，分別2801.5 cm-1、2082.9 cm-1及2805.0 cm-1，其甲醛頻譜2805.0 cm-1不會受水汽影響，可做為定量分析；並將光聲法及CNS1349 O1010進行比對及分析測值並代入檢量線之回歸方程式計算其結果， 進一步將此法使用在一般木質材料的甲醛逸散濃度量測上。本研究採用單板層積材（LVL）、中密度纖維板（MDF）兩種試材，光聲法頻譜分析結果發現LVL之甲醛濃度為671 mg／m^3（537ppmV）與MDF之甲醛濃度為10.6 mg／m^3（8 ppmV）。

關鍵字

揮發性有機物 ； 光聲法 ； 木質材料 ； 室內空氣品質

並列摘要

Wood is a porous material that has the ability to modulate the moisture and thermal performances. Therefore, wood based materials are often used in the construction and interior decorative of a building. However, the effects of volatile organic compounds (VOCs) from wood based materials have become a great concern of indoor air quality. The main purpose of this study is to investigate the formaldehyde by using the photoacoustic method to monitor and detect the wood based materials. Furthermore, it is important to understand how to prevent the formaldehyde emissions and the related impacts of formaldehyde concentrations on the indoor environment. For the real time detection of atmospheric formaldehyde with high sensitivity and excellent selectivity, the optical parametric oscillation (OPO) laser has been developed. The photoacoustic spectrum of formaldehyde was measured in the range from 2796 to 2806 cm^(-1) and an absorption line at 2805 cm^(-1) was selected for detection. The multipass acoustically open photoacoustic detector (MOPAD) combined with OPO lasers and the desiccator as the test cell for VOCs gas sensing in the atmosphere. High-resolution transmission molecular adsorption database HITRAN spectra for different water and formaldehyde concentrations were convolved with the IR lineshape function and were compared with that of the measured photoacoustic spectrum. Such a device could be an ideal tool for monitoring concentration changes in formaldehyde of wood based materials. Additionally, the concentrations of formaldehyde in LVL 671 mg/m^3(537 ppmV) and MDF 10.6 mg/m^3(8 ppmV) were recorded by the photoacoustic method.

並列關鍵字

Volatile organic compounds ； Photoacoustic method ； Wood based material ； Indoor air quality