Stannous tetra:fluoro-borate soln. prodn. from tin@ and fluoro-boric acid - in presence of oxygen@, using catalyst on fluoro-polymer-bound support giving pure soln. in acceptable reaction time, useful in electroplating

摘要

In the prodn. of Stannous tetrafluoroborate soln. (I) by reacting Sn with fluoroboric acid soln. in the presence of (gas contg.) oxygen and a catalyst (II), (II) consists of a catalytically active cpd. (III) on a support (IV) bound with a fluoropolymer (V). (III) is thermally treated N4-chelate, pyrolysed Co acetate-polyacrylonitrile or Pt, esp. 5-10 (wt.)% Pt; (IV) is activated charcoal, pref. activated with steam; and (V) is PTFE. Pref. Pt-coated (IV) is treated with a PTFE dispersion, esp. a very dil. dispersion, to give a PTFE content of 2-20, pref. 5-15 (wt.)%. (II) is used in an amt. of 0.01-5% w.r.t. Sn and Sn is used in stoichiometric excess. The reaction temp. is 30-90, pref. 80-85 deg.C. USE/ADVANTAGE - (I) is used in electroplating. (II) ensures very good contact between the Sn and fluoro-boric acid soln. (I) of high purity is obtd. and the process is not too time-consuming.