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70 Name: SULFURIC ACID (OIL OF VITRIOL) CAS No: 7664-93-9 Chemical Formula: H2SO4 Description: Hygroscopic, syrupy corrosive liquid. Use: NAS/CWTC 038/82 Formula Weight: 98.0 Used in pa adjustment following lime softening. Prepara- tion of activated silica from sodium silicate. Regenera- tion of resins. Purity Requirements . Analyses of available grades of sulfuric acid show the presence of selenium, arsenic, and lead. For arsenic and lead the levels are far below that which would necessitate RMIC values based on a maximum dosage of 50 mg/liter. If the actual dosage is other than 50 mg/liter, the user is cautioned to consult Table 2 for appropriate RMIC values. Impurity Selenium Analytical Sample Preparation: RMIC mg/Impurity/kg Sulfuric Acid 20 To an acid-washed 500-ml volumetric flask, add approxi- mately 250 ml of deionized water. Slowly, and with agitation, add 5 ml of sample to the water in the flask. Caution: Eye protection must be worn during this pro- cedure' Excessive heat buildup may result if sample is added to water too rapidly.
71 Sample Analyses: Analyze the sulfuric acid solution in accordance with Standards Methods for the Examination of Water and Waste- water, 15th Edition, American Public Health Association, Washington, D.C. (1980). Chromium Lead Selenium Section 304 Section 304 Section 304