Kinetic Study on the Hydrogen Reduction of Some Nonferrous Metal Oxides

To investigate the kinetic aspects in reactions involving solids, the reduction rate of nickel oxide by hydrogen was measured by means of thermo-balance. The rate is described by 2/3 order kinetic law and has an activation energy of 25 kcal/mol.. From the results of Delmon's interruption technique and other kinetic examination, it may be assumed that the reduction will proceed according to the spherical surface contracting model. The reduction rate of several ilmenite ores was also measured by the same means and the profiles of oxygen concentration in a section of reduced particles were examined by means of X-ray micro-analyser to inspect the reduction progress. It was found that the reduction process consists of two stages proceeding successively, where in the first stage, the reduction of iron oxide besides ilmenite component occurred, secondly, the latter component was reduced and those kinetics were also described approximately by 2/3 order law

Recent Developments in the Main Group Element Chemistry (SYNTHETIC ORGANIC CHEMISTRY-Synthetic Design)

Some recent advances in the main group element chemistry, especially in the organosilicon chemistry and the organoselenium chemistry, are described herein as follows: (1) Asymmetric intramolecular hydrosilation yielding an optically pure spirosilane with axial chirality, (2) high electron-transporting abilities of new silole p-conjugated compounds, and (3) effective steric protection of the selenium atom of the episelenonium ion intermediate

Thermodynamic Properties of Wustite (FeO₁₊y)

E.m.f. measurements of the cell, Pt/FeO₁₊y/ZrO₂ (CaO)/Ni-NiO/Pt, have been carried out to investigate the thermodynamic characteristics of wustite (FeO₁₊y). From these results, the relationship between temperature, oxygen pressure and composition of wustite and the phase boundaries of wustite phase in the binary system Fe-O were obtained and compared with those given by Darken and Gurry. The thermodynamic quantities such as activities of iron and oxygen in wustite, partial molar enthalpies and entropies of solution of oxygen in wustite and free energy of formation of magnetite were also evaluated. The defect sturcture of wustite was discussed in relation with the Po₂ dependence of cation vacancy concentration of wustite