Surface Technology , 23 (1984) 323 - 331 323 zyxwvutsr STRUCTURAL AND SURFACE PROPERTIES OF NICKEL OXIDE zyxwvutsrqponm AWAD I. AHMED Chemistry Department, Faculty of Science, M ansoura University, M ansoura (Egy pt) (Received February 15, 1984) zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJ Summary The effects of thermal treatment on both nickel hydroxide and nickel nitrate were studied by means of differential thermal analysis and X-ray analysis followed by nitrogen adsorption. The specific surface areas and pore size distributions were estimated. The surface area and pore volume increase with increasing temperature, to reach a maximum at 300 “C, and then de- crease. From the effects of the thermal treatment on the surface area it is concluded that the activation process is directly followed by a sintering process. The effects of the thermal treatment on the pore size distribution are also discussed. 1. Introduction Active metal oxides prepared by thermal decomposition of metal salts show different properties [1] depending on the chemical composition, the structure and the purity of the starting material. In addition, the atmosphere under which the activation is carried out, the temperature and the duration of the thermal treatment are important factors in determining the structural properties of the oxides. Transition metal oxides are well-known catalysts for a wide range of chemical reactions [ 2 - 61. The activity of such metal oxides can be improved and their lifetime can be increased by the addition of high melting point oxides. At present, attention is being focused on certain aspects of the phys- ical structure which characterize the “texture” of catalytic active oxides [ 71. These include the surface area, the pore geometry and the pore size distribu- tion. Nickel oxide and nickel oxide mixed with other oxides prepared by thermal decomposition of the hydroxide, carbonate and nitrate have been employed successfully for hydrogenation, dehydrogenation, dehydration reactions [ 8, 91, oxidation processes [ 10, 111 and in the cracking of heavy petroleum fractions [ 121, The effect of the electronic structure [13, 141 on the catalytic activity of nickel oxide catalysts has been the focus of interest of the majority of 0376-4583[84/$3.00 @ El~evier Sequoia/Printed in The Netherlands