Production and purification of titanium

摘要

In a process of producing titanium by the hydrogen reduction of titanium dihalide or a mixture of titanium di- and tri-halide (see Group II), the dihalide or mixed di- and tri-halide may be formed by passing gaseous titanium tetrahalide at appropriate conditions of temperature and pressure over metallic titanium or titanium-bearing material or by passing bromine, chlorine, hydrogen bromide or hydrogen chloride over metallic titanium or titanium-bearing material. In one example, a stream of argon was saturated with titanium tetrachloride vapour at 20 DEG C. and passed over small pieces (3-6 mesh) of impure titanium maintained at about 1150 DEG C. in a graphite reaction chamber lined with titanium sheet, the gaseous products containing titanium dichloride and argon. In a second example, titanium dibromide was produced by passing titanium tetrabromide at a partial pressure of 10 mm. over impure titanium in the same reactor and at the same pressure.ALSO:A process for the production of titanium consists in reducing the vapour of a titanium di-halide (chloride, iodide or particularly bromide), or of a mixture of titanium di- and trihalide, at elevated temperature with an excess of hydrogen to form titanium, which condenses, and hydrogen halide, which may be used for the further production of the applied titanium di-halide. The applied titanium di-halide may be formed by passing titanium tetrahalide over a titanium-bearing material, in an inert gas stream or in a partial vacuum, at an elevated temperature not exceeding the temperature of the subsequent hydrogen reduction. The applied titanium di-halide may also be formed by reacting a titanium-boaring material and a substance, e.g. bromine, chlorine, hydrogen bromide or hydrogen chloride, under conditions of temperature and pressure which will give rise to gaseous titanium di-halide. The temperature and pressure of the reduction are preferably chosen in order to reduce more than half the gaseous titanium di-halide so that condensation of any lower halide is prevented; if the reduction is considerably greater than 50 per cent, some of the titanium may be used for producing the titanium di-halide by passing titanium tetrahalide over it. The gaseous products from the reduction process (i.e. hydrogen, hydrogen halide, titanium tetra-halide and any lower titanium halides) may be treated, e.g. by fractional distillation, to remove the lower halides which are then converted to the tetrahalide by reaction with hydrogen halide or a halogen; the remainder is then treated in one of three ways: (a) by passing it over titanium-bearing material to form hydrogen and the tetrahalide, separating the constituents and re-applying the tetrahalide and the hydrogen to the process separately; (b) separating it into its constituents, e.g. by fraction distillation, reapplying the hydrogen and the tetrahalide to the process and reacting the hydrogen halide either with titanium-bearing material to form the dihalide which is recycled to the process or with titanium-bearing material (or carbon and a material containing titania) to form the tetrahalide, which is purified and recycled to the process; (c) by separating its constituents, returning the hydrogen and the tetrahalide to the process and converting the hydrogen halide, e.g. by means of oxygen, into the halogen which is then either reacted with titanium-bearing material (or titania and carbon) or with the lower halides to form the tetrachloride in each case.