建材中石綿之χ光繞射儀分析方法動態

石綿為一群水合纖維狀矽酸鹽礦物之總稱，主要分成蛇紋石與角閃石兩大類，蛇紋石又以白石綿為代表，角閃石則有青石綿、褐石綿、斜方角閃石、透閃石與揚起石等。石綿本身具有耐高溫、耐酸鹼、耐磨、抗拉力、抗腐蝕、絕熱和絕緣等特性，所以廣泛運用於製造建材、絕緣體及煞車來令片總數等超過3,000種以上產品。本研究針對檢測建材中微量石綿含量，以χ光繞射儀分析，定量時以鋅板為基底標準吸收補正法為佳，在粗細粒徑以100mesh過濾的細顆粒檢測強度可增強13.4%。樣品前處理以40mL無塵水及20%蟻酸濃度在25℃水浴的條件下，比30℃的檢測強度高14.9%。樣品於水浴中消化處理時間，以震盪10分鐘後靜置12分鐘後，再以25mm T60A20濾紙加過濾，為最佳的消化處理時間。在白石綿及褐石綿的標準偏差值或變異係數值也都比現行方法較佳，白石綿和褐石綿的檢測值結果更提高至31.7%、38.5%。本研究不僅可提供批次多樣品的前處理能力，更是高效率、簡便、省時、精確、經濟的分析方法。

關鍵字

石綿；蟻酸； χ光繞射儀

並列摘要

Asbestos is a natural mineral consisting of fibrous shape salts of hydrous silicates. It can be classified into two groups: (1)serpentine that includes chrysotile, etc.; (2) amphibole that includes amosite, crocidolite, anthophyllite, actinolite and tremolite, etc. There are thousands of asbestos products for wide industrial application. The study aimed at testing the alternative quantitative method to accurately determine the asbestos content in sample building materials. X-ray Diffraction (XRD) was used for quantitative sample analysis in this study. In addition, tests were conducted with different pore sizes, acid concentrations, hot water baths and various shaking procedure to determine the most effective quantitative processes for asbestos content analysis in sample material. The results indicated that accuracy of quantitative measurements could be improved by: 1. Pre-filtering the sample with filters of 100 meshes indicated a 13.4% improvement of the quantitative measurements. 2. Test samples were pretreated with 20ml 20% formic acid and 40ml DI-water(clean) and then heated in the 25℃ hot-water bath. With a 10 minutes shaking and 12 minutes stabilizing, test samples were treated by suction filtration process on a 25mm T60A20 filter paper. Testing outcome indicated a 14.9% improvement in quantitative measurements pretreated at 25℃℃ than at 30℃. 3. Standard deviation as well as the coefficient of variation of chrysotile and amosite measurements indicated improving outcome than the present methods. Meanwhile, quantitative measurements of chrysotile and amosit concentrations in test samples increased by 31.7% and 38.5%, individually. In summary, this study has proved our pretreatment test method to be valid in preparing multiple asbestos samples instantaneously. The method also offers high quantitative accuracy and efficiency, time-saving and cost-saving as well.

並列關鍵字

Asbestos ； Formic acid ； XRD

參考文獻

Craighead, J.E.,Abraham, J.L.,Churg, A.,Green, F.H.,Kleinerman, J.,Partt, P.C.(1982).The pathology of asbestos-associated diseases of the lungs and pleural cavities: diagnostic criteria and proposed grading schema.Archives of Pathology and Laboratory Medicine.106,544-96.