REMOVAL OF CONTAMINANTS FROM GAS STREAMS IN RAYON PRODUCTION

摘要

Sulfurous gas streams comprising hydrogen sulfide and carbon disulfide, such as produced as a by-product of the rayon-forming process, are processed to recover the components in a useable form. The gas stream first is contacted with an aqueous sodium hydroxide to dissolve out hydrogen sulfide and some of the carbon disulfide. The dissolved carbon disulfide is driven off from the solution and condensed as a liquid concentrate. Carbon disulfide receiving in the gas stream is recovered, such as by condensation. The aqueous sodium sulfide solution which remains is concentrated and the pH is adjusted, as necessary, to a value at which the sodium sulfide is predominantly in the form of sodium bisulfide. The concentrated sodium bisulfide solution is capable of reuse in the rayon-forming process along with the liquid concentrate of carbon disulfide.