Prepn of germanium phosphite useful as a catalyst in

摘要

Germanium (II) phosphite is prepd. by reacting germanium (IV) oxide, hypophosphoric acid and phosphoric acid in a ratio of 1:1: is not => in the pres. of 200-800 cm3 (pref. 300-500 cm3) water per mol germanium (IV) oxide, at 50-100 deg.C (pref. 70-95 deg.C) until reaction is complete, (is not => 4 hrs), removing the crystalline deposit of germanium (II) phosphite and repeating the reaction several times in the same mother liquor by the addition of fresh germanium (IV) oxide and hyphophosporous acid. Catalyst in the prepn. of polyethylene terephthalate.