Abstract: A process for extracting metal values especially zinc values from aqueous solutions of metal salts which comprises contacting the aqueous solution with an organic phase comprising a compound of the formula: ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently, represents an optionally substituted hydrocarbyl or hydrocarbyloxy group or R.sup.1 and R.sup.2 together with the attached phosphorus atom and/or R.sup.3 and R.sup.4 together with the attached phosphorus atom form a 5- to 8-membered heterocyclic ring.

Abstract: A process for extracting metal values especially zinc values from aqueous solutions of metal salts which comprises contacting the aqueous solution with an organic phase comprising a compound of the formula: ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently, represents an optionally substituted hydrocarbyl or hydrocarbyloxy group or R.sup.1 and R.sup.2 together with the attached phosphorus atom and/or R.sup.3 and R.sup.4 together with the attached phosphorus atom form a 5- to 8-membered heterocyclic ring.

Abstract: A process for extracting metal values especially zinc values from aqueous solutions of metal salts which comprises contacting the aqueous solution with an organic phase comprising a compound of the formula: ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently, represents an optionally substituted hydrocarbyl or hydrocarbyloxy group or R.sup.1 and R.sup.2 together with the attached phosphorus atom and/or R.sup.3 and R.sup.4 together with the attached phosphorus atom form a 5- to 8-membered heterocyclic ring.

Abstract: A process for extracting metal values especially zinc values from aqueous solutions of metal salts which comprises contacting the aqueous solution with an organic phase comprising a compound of the formula: ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently, represents a substituted hydrocarbyl or hydrocarbyloxy group or R.sup.1 and R.sup.2 together with the attached phosphorus atom and/or R.sup.3 and R.sup.4 together with the attached phosphorus atom form a 5- to 8-membered heterocyclic ring.

Abstract: A solvent soluble heterocyclic o-hydroxy thione carrying a lipophilic group and the process for the selective extraction of gallium, and certain other related metals, especially from solutions containing excess aluminium.

Abstract: Gallium is efficiently extracted from strongly basic solutions containing aluminates by extractants having the tris- and/or tetrakis(2-hydroxybenzyl)-1,2-diaminoethane chemical moiety. The diaminoethane derivative may be used together with a hydrocarbyl 8-hydroxyquinoline and/or with a tertiary carboxylic acid.

Abstract: A composition of bibenzimidazoles of the Formula (I): ##STR1## wherein X & Y which may be the same or different and, taken together, contain a total of from 12 to 52 saturated carbon atoms, are (a) each selected from --R, --COR, --CH.sub.2 COOR, --CH(COOR).sub.2 and --COOR; or (b) together form a group selected from ##STR2## wherein R is an optionally substituted hydrocarbyl group,A & B taken together with the two carbon atoms to which they are linked form an optionally substituted benzene ring; andC & D taken together with the two carbon atoms to which they are linked form an optionally substituted benzene ring;characterised in that at least 50% by weight of the bibenzimidazoles in the composition are of Formula (II) ##STR3## wherein X and Y are as hereinbefore defined;T, U, V & W which may be the same or different, are H, R.sup.1 or OR.sup.1 provided at least one of T, U, V & W is R.sup.1 or OR.sup.1 ;and R.sup.1 is C.sub.

Abstract: Metal values, especially copper values, are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by a 1,2,4 triazole substituted in the 1-position by (1) a hydrocarbyl (alkyl) group or (2) a group of the formula --(X).sub.n --(CO--Y).sub.m where X is an optionally substituted methylene, vinylene or phenylene linking group or a linking group of formula --CO--A-- where A is an optionally substituted aromatic ortho linking group; n is 0 or 1; Y is OR.sub.2 or R.sub.3 where R.sub.2 and R.sub.3 are hydrocarbyl groups containing from 5 to 36 carbon atoms (preferably branched alkyl groups containing from 9 to 24 carbon atoms); and m is from 1 to 3.

Abstract: Gallium is efficiently extracted from strongly basic solutions containing aluminates by extractants having the tris- and/or tetrakis (2-hydroxybenzyl)-1,2-diaminoethane chemical moiety. The diaminoethane derivative may be used together with a hydrocarbyl 8-hydroxyquinoline and/or with a tertiary carboxylic acid.

Abstract: A process for extracting metal values such as gallium and/or indium from aqueous solutions by contacting said solutions with a water immiscible organic solvent having dissolved therein a heterocyclic thione.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyridine derivatives containing the substituent --(COX).sub.A where X is the group --OR.sub.1 or --NH.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 5 to 36 carbon atoms and R.sub.2 and R.sub.3 are hydrogen or a hydrocarbyl group wherein R.sub.2 and R.sub.3 together contain from 5 to 36 carbon atoms. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores such as chalcopyrite.

Abstract: Metal values, especially copper values, are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by a 1,2,4 triazole substitued in the 1- position by (1) a hydrocarbyl (alkyl) group or (2) a group of the formula --(X).sub.n --(CO--Y).sub.m where X is an optionally substituted methylene, vinylene or phenylene linking group or a linking group of formula --CO--A-- where A is an optionally substituted aromatic ortho linking group; n is 0 or 1; Y is OR.sub.2 or R.sub.3 where R.sub.2 and R.sub.3 are hydrocarbyl groups containing from 5 to 36 carbon atoms (preferably branched alkyl groups containing from 9 to 24 carbon atoms); and m is from 1 to 3.

Abstract: Metal values are extracted from aqueous solutions containing halide or pseudohalide anion using 1,1'-substituted 2,2'-biimidazole or bibenzimidazole compounds. Useful for the solvent extraction of zinc and copper from chloride leach solutions.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyridine derivatives containing the substituent --(COX).sub.A where X is the group --OR.sub.1 or --NR.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 5 to 36 carbon atoms and R.sub.2 and R.sub.3 are hydrogen or a hydrocarbyl group wherein R.sub.2 and R.sub.3 together contain from 5 to 36 carbon atoms. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores such as chalcopyrite.

Abstract: Metal values are extracted from aqueous solutions containing halide or pseudohalide anion using 1,1'-substituted 2,2'-biimidazole or bibenzimidazole compounds. Useful for the solvent extraction of zinc and copper from chloride leach solutions.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyridine derivatives containing the substituent --(COX).sub.A where X is the group --OR.sub.1 or --NR.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 5 to 36 carbon atoms and R.sub.2 and R.sub.3 are hydrogen or a hydrocarbyl group wherein R.sub.2 and R.sub.3 together contain from 5 to 36 carbon atoms. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores such as chalcopyrite.

Abstract: Metal values, particularly copper values, are extracted from aqueous solutions containing halide or pseudohalide anion using 6,7 substituted triazolopyrimidine wherein the 6-substituent is a group --CO--OR1 where R1 is a hydrocarbyl group containing from 1 to 35 carbon atoms, preferably an alkyl group and wherein the 7-substituent (R2) is hydrogen or a hydrocarbyl group containing from 1 to 35 atoms wherein R1 and R2 taken together contain a total of from 5 to 35 saturated carbon atoms.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyrimidine, pyrazine or pyridazine derivitives bearing the substituent --(C.dbd.O.X).sub.n where X is the group --OR.sub.1 or --NR.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 1 to 36 carbon atoms and R.sub.2 and R.sub.2 together contain from 1 to 36 carbon atoms. The molecule as a whole contains from 5 to 36 alkyl carbon atoms and may carry further optional substituents. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyridine derivatives containing the substituent --(COX).sub.A where X is the group --OR.sub.1 or --NR.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 5 to 36 carbon atoms and R.sub.2 and R.sub.3 are hydrogen or a hydrocarbyl group wherein R.sub.2 and R.sub.3 together contain from 5 to 36 carbon atoms. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores such as chalcopyrite.

Abstract: Process for disperse azo dyes having a cyano radical ortho to the azo group by reacting the corresponding halogeno dye with a covalent non-metallic nitrile in the presence of a copper catalyst and an acid acceptor. Previous processes have used a metal cyanide as the cyanide source. The present process does, however, contemplate the use of a non-metallic nitrile, even in small amounts, in combination with a metal cyanide for which advantages are to be gained in terms of reduced copper usage. The non-metallic nitrile is preferably a cyanohydrin which may be prepared in situ by reacting an aldehyde or ketone with a metal cyanide. The metal cyanide may itself provide the copper catalyst.