Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection
Powder X-ray diffraction (XRD) is a widely accepted technique for detecting trace asbestos content in solid samples. However, accurately quantifying asbestos concentrations below 0.5 wt% presents significant challenges with XRD alone. To address this limitation, we conducted a meticulous quantitativ...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-01-01
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| Series: | Crystals |
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| Online Access: | https://www.mdpi.com/2073-4352/14/2/127 |
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| author | Sasithorn Chornkrathok Przemyslaw Dera Phuong Q. H. Nguyen Robert T. Downs |
| author_facet | Sasithorn Chornkrathok Przemyslaw Dera Phuong Q. H. Nguyen Robert T. Downs |
| author_sort | Sasithorn Chornkrathok |
| collection | DOAJ |
| description | Powder X-ray diffraction (XRD) is a widely accepted technique for detecting trace asbestos content in solid samples. However, accurately quantifying asbestos concentrations below 0.5 wt% presents significant challenges with XRD alone. To address this limitation, we conducted a meticulous quantitative analysis using XRD on synthetic samples of talc-based powder spiked with varying amounts of natural tremolite and anthophyllite asbestos. At concentrations exceeding 0.5 wt%, both tremolite and anthophyllite displayed distinct XRD peaks. Yet, at lower concentrations (0.1 wt% and 0.05 wt%), the diffraction peaks of the contaminants became less prominent. To improve detection sensitivity, we explored different protocols of heavy liquid separation utilizing sodium polytungstate (SPT) to concentrate asbestos relative to the other mineral components. The optimized protocol, employing SPT with a density of 2.89 g/cm<sup>3</sup>, effectively separated amphibole asbestos from lighter, commonly associated minerals, like talc, clinochlore, and mica. Subsequent powder XRD analysis of the heavy fraction confirmed the successful removal of non-target materials, enhancing the diffraction peaks of tremolite and anthophyllite. Tremolite exhibited comparatively less weight loss than anthophyllite during this separation process. This study establishes the theoretical and practical viability of employing centrifugation in a heavy liquid to separate tremolite and anthophyllite from talc, providing valuable insights for asbestos detection and quantification in challenging scenarios. |
| first_indexed | 2024-03-07T22:37:01Z |
| format | Article |
| id | doaj.art-e179f87253424cb2be9897a403550ac7 |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-03-07T22:37:01Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
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| series | Crystals |
| spelling | doaj.art-e179f87253424cb2be9897a403550ac72024-02-23T15:13:09ZengMDPI AGCrystals2073-43522024-01-0114212710.3390/cryst14020127Heavy Liquid Separation Method for Enhancement of Trace Asbestos DetectionSasithorn Chornkrathok0Przemyslaw Dera1Phuong Q. H. Nguyen2Robert T. Downs3Department of Earth Sciences, University of Hawaiʻi at Mānoa, Honolulu, HI 96822, USAHawaiʻi Institute of Geophysics and Planetology, University of Hawaiʻi at Mānoa, Honolulu, HI 96822, USAHawaiʻi Institute of Geophysics and Planetology, University of Hawaiʻi at Mānoa, Honolulu, HI 96822, USADepartment of Geosciences, University of Arizona, Tucson, AZ 85721, USAPowder X-ray diffraction (XRD) is a widely accepted technique for detecting trace asbestos content in solid samples. However, accurately quantifying asbestos concentrations below 0.5 wt% presents significant challenges with XRD alone. To address this limitation, we conducted a meticulous quantitative analysis using XRD on synthetic samples of talc-based powder spiked with varying amounts of natural tremolite and anthophyllite asbestos. At concentrations exceeding 0.5 wt%, both tremolite and anthophyllite displayed distinct XRD peaks. Yet, at lower concentrations (0.1 wt% and 0.05 wt%), the diffraction peaks of the contaminants became less prominent. To improve detection sensitivity, we explored different protocols of heavy liquid separation utilizing sodium polytungstate (SPT) to concentrate asbestos relative to the other mineral components. The optimized protocol, employing SPT with a density of 2.89 g/cm<sup>3</sup>, effectively separated amphibole asbestos from lighter, commonly associated minerals, like talc, clinochlore, and mica. Subsequent powder XRD analysis of the heavy fraction confirmed the successful removal of non-target materials, enhancing the diffraction peaks of tremolite and anthophyllite. Tremolite exhibited comparatively less weight loss than anthophyllite during this separation process. This study establishes the theoretical and practical viability of employing centrifugation in a heavy liquid to separate tremolite and anthophyllite from talc, providing valuable insights for asbestos detection and quantification in challenging scenarios.https://www.mdpi.com/2073-4352/14/2/127heavy liquid separationpowder X-ray diffractionsodium polytungstatetremoliteanthophyllitetalc-based powder |
| spellingShingle | Sasithorn Chornkrathok Przemyslaw Dera Phuong Q. H. Nguyen Robert T. Downs Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection Crystals heavy liquid separation powder X-ray diffraction sodium polytungstate tremolite anthophyllite talc-based powder |
| title | Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection |
| title_full | Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection |
| title_fullStr | Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection |
| title_full_unstemmed | Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection |
| title_short | Heavy Liquid Separation Method for Enhancement of Trace Asbestos Detection |
| title_sort | heavy liquid separation method for enhancement of trace asbestos detection |
| topic | heavy liquid separation powder X-ray diffraction sodium polytungstate tremolite anthophyllite talc-based powder |
| url | https://www.mdpi.com/2073-4352/14/2/127 |
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