Feasibility of recovering metals from associated slags
The associated mineral ore accompanying Valuable Metal Compounds (VMC) have been usually treated in a smelting furnace ,such as Blast Furnace, Reverberatory, Blowing Furnace, hence the VMC were mostly concentrated into the molten associated slags and separated from liquid metals. So the associated slags become an important man-made resources (Table I), in which the VMC exist dispersively in various mineral phases with fine grain size1–4. Due to complex mineralogy and very fine mineral dissemination of the associated slags, it is difficult to recovery the VMC from the slags by metallurgical or mineral process conventionally . Based on several case studies in laboratory and practices in pilot plant on the associated slags , there occur a feasibility to recovery the VMC from the slags by a new process-Selective Precipitation Technique (SPT) on which three continuous steps are involved (in Figure 1).
A Study on Acidolysis of Perovskite by H_2SO_4
A systematical laboratory study is made of the effects of dosage and concentration of H 2SO 4, particle size of perovskite and reation temperature and time on acidolysis ratio of titanium in perovskite. At a H 2SO 4 concentration of 90%, suitable experiemental conditions for acidolysis of perovskite are as follows: a perovskite to H 2SO 4 ratio of 6∶35 02, a reaction temperature of 100 ℃ and a reaction time of 1 5 h. Under such conditions, acidolysis ratio of titanium in perovskite is up to 100%, and formation of TiO 2 precipitate and hytrolysis of TiO 2 2+ can be avoided. The dependence of acidolysis ratio of tianium on time under the above conditions is imitated. The imitation equation is X=-2 27×10 -3 t+5 27×10 -4 t 2-4 2×10 -6 t 3 .
Nucleation, growth and coarsening of γ′-precipitates in Ni-5.0 at.% Al-5.8 at.% Ti
Abstract The decomposition kinetics of supersaturated Ni-5.0 at.% Al-5.8 at.% Ti was investigated after isothermal annealing in the temperature range between 773 and 1023 K by the use of small angle neutron scattering, field ion microscopy with atom probe, and transmission electron microscopy. In the initial phase of the decomposition reaction the morphology of the γ′-phase is characterized by spherical precipitates. A very sluggish growth of the γ′-precipitates was observed over up to four orders of magnitude in time (773 K:R∝t0.18; 823 K: R∝t0.25). The late stages of decomposition are characterized by an increase in the mean particle size proportional to t 1 3 . Cubes with rounded corners formed, which were preferentially aligned along 〈100〉. The origin of these behaviours is discussed qualitatively in terms of nucleation, growth and coarsening.