Low zirconium, hafnium-containing compositions, processes for the preparation thereof and methods of use thereof

A process for producing a composition comprising a hafnium-containing compound represented by the formula Hf(R)m wherein R is the same or different and represents a halogen atom, a pseudohalogen group, an acyl group having from 1 to about 12 carbon atoms, an alkoxy group having from 1 to about 12 carbon atoms, an alkoxycarbonyl group having from 1 to about 12 carbon atoms, an alkyl group having from 1 to about 12 carbon atoms, an amino group having from 1 to about 12 carbon atoms, an imino group having from 1 to about 12 carbon atoms, a silyl group having from 0 to about 12 carbon atoms, an allyl-like group having from 1 to about 12 carbon atoms, a beta-diketonato group having from 1 to about 12 carbon atoms, or an amidinato group having from 1 to about 12 carbon atoms, m is a value of from 1 to 4, and wherein said composition has a zirconium concentration of less than about 500 parts per million, which process comprises reacting a hydrocarbon or heteroatom-containing compound with a hafnium halide compound represented by the formula Hf(X)4 wherein X is the same or different and is a halide and wherein said hafnium halide compound has a zirconium concentration of less than about 500 parts per million, under reaction conditions sufficient to produce said composition;

• wherein said hafnium halide compound is produced by a process which consists essentially of (i) reacting a hafnium oxide compound, wherein said hafnium oxide compound has a zirconium concentration of less than about 500 parts per million, with a halogen or halogen-containing compound in the absence of air and moisture and under reaction conditions sufficient to produce said hafnium halide compound, (ii) purifying said hafnium halide compound to remove organic impurities, and (iii) recovering said hafnium halide compound without air or moisture exposure.