摘要 |
The invention relates to a process for purifyng crude gaseous hydrogen chloride originating from plants producing silane or siloxane and containing as impurities silanes which contain chlorine and/or organic radicals, water, alkanols, hydrocarbons, chlorinated hydrocarbons, organic acids and derivatives thereof, by condensation, compression and fractional distillation. In this process, the crude gas is at least partially freed from condensable products by cooling to -35 DEG C., then compressed in a screw compressor with oil injection to 1.5 MPa, the oil is separated off, freed from gel-containing residues through a filter web and again recycled into the compressor. The compressed hydrogen chloride gas is fractionated in a distillation column under pressure and hydrogen chloride having a purity of 99.999 percent is recovered.
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