Abstract: A method for the manufacture of crystal water-free iron(II) orthophosphate of the general formula Fe3(PO4)2 or crystal water-free iron(II) metal orthophosphate, iron(II) metal pyrophosphate or iron(II) metal metaphosphate of the general formula FeaMetb(POc)d, where a is a number from 1 to 5, b is a number from >0 to 5, c is a number from 2.5 to 5, d is a number from 0.5 to 3 and Met represents one or more metals selected from the group consisting of K, Rb, Cs, Mg, Ca, Sr, Ba, the transition metals (d block), in particular Sc, Y, La, Ti, Zr, Hf, Nb, Ta, Cr, Mo, W, Mn, Cu, Zn and the metals and semimetals of the third, fourth and fifth main groups, in particular B, Al, Ga, In, Si, Sn, Sb, Bi and the lanthanoids.

Abstract: A method for the manufacture of crystal water-free iron(II) orthophosphate of the general formula Fe3(PO4)2 or crystal water-free iron(II) metal orthophosphate, iron(II) metal pyrophosphate or iron(II) metal metaphosphate of the general formula FeaMetb(POc)d, where a is a number from 1 to 5, b is a number from >0 to 5, c is a number from 2.5 to 5, d is a number from 0.5 to 3 and Met represents one or more metals selected from the group consisting of K, Rb, Cs, Mg, Ca, Sr, Ba, the transition metals (d block), in particular Sc, Y, La, Ti, Zr, Hf, Nb, Ta, Cr, Mo, W, Mn, Cu, Zn and the metals and semimetals of the third, fourth and fifth main groups, in particular B, Al, Ga, In, Si, Sn, Sb, Bi and the lanthanoids.

Abstract: A process for the removal of cadmium ions by liquid-liquid extraction from wet process phosphoric acid, which had been obtained from crude phosphate ores by dissolution with sulfuric acid, uses salts of long chain alkyl amines or ammonium bases with the chlorocomplexes of polyvalent metal ions, which are dissolved in an inert organic solvent.

Abstract: Disclosed is a process for the precipitation and separation of cadmium sulphide from the raffinates derived from phosphoric acid purification by treating the cadmium containing streams of the raffinates with a H.sub.2 S containing solvent phase in a mixing-settling apparatus, by separating the raffinate phase from the cadmium sulphide containing solvent phase and by separating the precipitated cadmium sulphide from the solvent phase. By operating this process it is possible to remove cadmium in a simple manner from the raffinates since their inherent properties don't influence the precipitation and separation of cadmium sulphide.

Abstract: The invention is concerned with a process of removing cadmium from acid, especially P.sub.2 O.sub.5 -containing solutions by liquid/liquid extraction with the aid of alkyl amine salts that are dissolved in an inert, organic solvent. The cadmium ions are removed from the acid, aqueous phase and are enriched in the organic phase. The cadmium-containing organic phase, subsequently, is re-extracted with an aqueous salt solution, with the cadmium ions migrating from the organic phase into the aqueous phase. The process is particularly suitable for extracting cadmium from concentrated, highly acid aqueous solutions.