Journal of the Research Institute for Catalysis, Hokkaido University 

About: Journal of the Research Institute for Catalysis, Hokkaido University is an academic journal. The journal publishes majorly in the area(s): Catalysis & Hydrogen. It has an ISSN identifier of 0034-530X. Over the lifetime, 322 publications have been published receiving 1180 citations.

Periodic variation of exchange current density of hydrogen electrode reaction with atomic number

Abstract: The works on hydrogen electrode reaction have been increasingly accumulated during the last decade. These works are much more reliable than earlier ones, in­ asmuch as the special precaution has been taken against contaminations of solution and electrode surface. Survey of the results shows that the activity of metals for the reaction in terms of the exchange current density, io (Acm -2), varies in a wide range, namely from log io = -1.2 on Pd to -12.9 on Pb and even on the same metal, from -3.15 to -7.04 on Au (ef Table 1). Such variations in the activity may be caused by several factors such as bulk property of electrode material, surface state of the electrode and solution. The present note is concerned with the relation of the exchange current density of various metals to their position in the Periodic Table and with the decision of the determining factor of the activity.

Basicity and acidity of solid surfaces

Abstract: A method has been developed for the determination of the basicity of solid surfaces which consists of the titration of the solid suspended in benzene with benzoic acid, using bromthymol blue as the indicator. Surface basicity of MgO and CaO was determined by this method to be 0.033 and 0.007 mmoles/g respectively and the basicity of these solids found to be changed remarkably by heat-treatment. MgO showed a maximum basicity of 0.069 mmoles/g when treated at 500°C before the basicity measurements and the basicity of CaO treated at 650°C was found to be ten times as large as that of untreated one. No reliable data were obtained for the basicity of K2C03, Na2C03 and Na2C03·lOH20 due to the strong hydrolyses. ZnO and ZnS which were reported to be solid bases by KRILOV et al. and NISHIMURA showed no basic property in this method. ZnO showed a slight acidity of 0.004 mmoles/g at acid strength Ho-:;;;' +6.8, and ca. 0.010 mmoles/g at the same acid strength when heated in air or in vacuum. High acidity was observed for ZnS, i. e., 0.773 mmoles/g at Ho-:;;;' +6.8, 0.355 mmoles/g at Ho-:;;;' +4.8 and 0.092 mmoles/g at Ho-:;;;' +4.0. The acidity changed on heat-treatment and maximum acidities 2.77-1.45 mmoles/g at acid strength range, +3.3

Chemisorption and catalytic activity of a set of platinum catalysts

Abstract: Procedures have been developed for the preparation of mono disperse platinum sols by the· reduction of chloroplatinate ion by citrate ion, for hydrothermal preparation of ultramicroscopic alumina plates and for the preparation from these of platinum on alumina catalysts. These catalysts and· platinum on silica catalysts prepared both by impregnation and ion exchange and obtained from Professor BURWELL were characterized by high resolution electron microscopy, electron diffraction, chemisorption and determination of active centers for ethylene hydrogenation by poison titration with sulphur compounds. Good relationship for the number of surface atoms was obtained between electron microscopy and hydrogen chemisorption. However the number of active centers for hydrogenation was found to be a fraction of the number of surface atoms determined by hydrogen chemisorption. Platinum sols of varying sedimentation constants were found to have varying catalytic activity for hydrogen peroxide decomposition and this activity paralleled their light absorbance in solution before coagulations set in.