以固態擴散法偵測空氣中丙酮及丁酮之研究

Diffusive sampling onto solid Adsorbents for Monitoring Acetone and Methyl Ethyl ketone in Air

丙酮與丁酮在工業界用途廣，用量多，如果使用不當則對廣大從業勞工之健康將有不利的影響。因此有關勞工作業環境空氣中丙酮與丁酮之測定向為各界所重視。傳統上空氣中丙酮與丁酮的測定方法多以主動式個人採樣，即分別以活性碳管及矽膠管來採集丙酮與丁酮，再分別以二硫化碳及DMSO來脫附，最後再以氣相層析法來分析。由於此種方法需利用到兩種固體吸附管及不同脫附劑來進行，且受測者需配戴採樣泵，故在環境測定上不但費時費力，且勞工有時也不願配合，因此，本計劃乃利用被動式採樣原理，以裏覆有0- （2,3,4,5,6-pentafluorobenzyl） -hydroxylamine hydrochloride（即簡稱PFBOA）固體吸附材質來採樣，其結果如下：一、PFBOA可同時與丙酮及丁酮反應產生穩定之衍生物。二、經GC-MASS鑑定此等衍生物之分子量分別為253及267，而Q由理論推估及丙酮及丁酮衍生物的分子量也剛好與此相同。三、將PFBOA裏覆在玻璃纖維濾紙後，再放入長5公分，直徑為2.5公分採樣匣內，經初步實驗結果，認為它應可做為丙酮及丁酮之被動式採樣之用。四、前述衍生物經正已烷萃取後可由氣相層析法加以分析之。

A simple, sensitive and specific diffusive sampler for monitoring of airborne acetone and metyl ketone (MEK) is described, based on the chemical derivation of ketones and 0 – (2,3,4,5,6 pentafluorobenzyl) hydroxylamine hydrochloride (PFBOA). In this study, acetone and MEK is sampled from air by diffusion into a 25MM glass fiber filter impregnated with PFBOA mounted in a commercially available cassette (SKC-255-3-12). The corresponding oxime formed is desorbed from the filter with n-hexane and determined by gas chromatograph equipped with flame ionization detector. The preliminary results are summarized as follows: 1. With the help of wet pad, PFBOA coated on glass fiber can quantitatively react with airborne acetone and MEK. 2. The corresponding derivatives formed can store at 4℃ for more than four weeks without significantly changing of their concentrations. 3. The mass septram show that the molecular weight of acetone and MEK derivatives are 253 and 267, respectively. 4. Under experimental condition in exposure chamber, the described diffusive sampler adsorbed airborne acetone and MEK in a manner linear to exposure concentrations-changed from 1/4 TLV to 2 TLV. 5. By spiking acetone and MEK onto the glass fiber filter impregnated with PFBOA, the detection limit of acetone and MEK are 0.00016 mg and 0.006578 mg in 1ml n - hexane solution extracted from the filter, respectively.