Hoechst Aktiengesellschaft

Ulrich Girrbach

Egon Malow

Edgar Hartl

Siegbert Rittner

Klaus Schmiedel

Richard Grimm

Siegfried Bildstein

The invention provides a process for the selective absorption of chlorine and/or bromine from CO.sub.2 -containing off-gases. The off-gas must contain at least 1 mol of SO.sub.2 per mol of Cl.sub.2 and/or per mol of Br.sub.2 ; if necessary sufficient SO.sub.2 is added to the off-gas to give the above-mentioned relative amount. Chlorine and/or bromine is absorbed by mixing the off-gas with steam and then cooling the mixture until the steam condenses. An example of a suitable apparatus is a vertical tube having an internal cooling coil.

Process for the selective absorption of chlorine and/or bromine from

The invention provides a process for the selective absorption of chlorine from CO.sub.2 -containing off-gases, which comprises washing the off-gases with an aqueous solution which contains 0.1-10% by weight of NaHCO.sub.3 and 0.01-5% by weight of NaHSO.sub.3.

Process for the selective absorption of chlorine from CO.sub.2

The invention relates to a process for the separation and recovery of naphthalenesulfonic acids from aqueous solutions. In this, the naphthalenesulfonic acids are adsorbed on basic ion exchangers and subsequently desorbed again, preferably with the aid of an alkaline liquor, from which the alkali metal sulfonates are then precipitated by cooling.

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Frankfurt am Main, Germany

Ulrich Girrbach