Hydrochloric acid was once used to retrieve metals from rock, but many firms abandoned it for cost reasons for cyanide.

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Working with his students, Butz twice soaked the samples in a weak solution of hydrochloric acid to remove any contemporary soot stains.

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They are exploring plant sites for processing the ore in the United States adjacent to a chemical facility that produces hydrochloric acid.

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The drums, containing hydrochloric acid and sulphuric acid, were stolen from the business in Whitecroft, and later recovered from a property in the same village.

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Fracking fluids are believed to contain, in addition to water, benzene, ethylbenzene, formaldehyde, methanol, naphthalene, polycyclic aromatic hydrocarbons, toluene, xylene, boric acid, hydrochloric acid, isopropanol, and diesel fuel.

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These are the first national standards to require use of modern control technologies to reduce mercury, arsenic, lead, hydrochloric acid and other hazardous air pollutants from coal plants.

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The violations stemmed from an inspection last summer that revealed an alleged failure to provide workers handling hydrochloric acid and other dangerous materials with the necessary protection for face, hands and eyes.

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