| 摘要 |
A method for quantitative analysis of asbestos in vermiculite-containing materials includes a first embodiment which includes washing the sample with water or treating the sample with a low concentration acid to digest gypsum and carbonates, ashing the sample at a low temperature to remove cellulose, therefrom and analyzing the sample. Digestion may be effected before or after ashing. Subsequently, a second subsample may be ashed at low temperature to remove cellulose and refluxed with a concentrated acid followed by refluxing with a base and rinsing with deionized water to wash away gypsum, vermiculite and other soluble components. This is followed by analysis to determine asbestos concentration. In a further embodiment, the residue if the first embodiment may be employed as the second subsample. |
| 主权项 |
1. A method for quantitative analysis of asbestos in a vermiculite-containing material comprising,
providing a sample of said vermiculite-containing material, placing said vermiculite-containing material in filtering apparatus, treating said sample with a material selected from the group consisting of water and an acid selected from the group consisting of HCl, HBr, HCrO4, H2SO4, HNO3, citric acid, acetic acid, and formic acid, in a concentration of about 0.1 N to 1.5 N, washing the sample with water, dry said washed sample, determine the weight loss of said sample, ash the residue at about 450° C. to 550° C. for about 1 to 3 hours, cool said sample, determine ash weight loss, employing water to transfer the residue to a filter, dry the residue, calculate the percentage weight loss, and analyze the sample to determine the quantity of asbestos in said vermiculite-containing material, whereby cellulose, gypsum and carbonates have been removed from said sample prior to said analysis. |
