Two membrane-rdated research projects are now being developed in Japan and their main target is to develop new inorganic membranes. The first project is the R & D of membranes for carbon dioxide recovery at high temperature, conducted by the Japan Fine Ceramics Center (JFCC) and Japan Fine Ceramics Association (JFCA) under the supervision by the New Energy and Industrial Technology Development Organization (NEDO). The second one is the R & D of membranes for petroleum refinery and chemical processes, conducted by the Japan High Polymer Center (JHPC) under the supervision by the Petroleum Energy Center (PEC). Cooperating with these projects researchers in many universities and research institutes have been publishing many interesting data of inorganic membranes manufactured by various methods. Many such results are summarized and reported.

Since the discovery of the Loeb-Sourirajan reverse osmosis membrane, thirty years have passed and many membrane technologies and new membranes for applications have been developed in the world. In the early stage of these developments Japan has not contributed much, but from the middle of 70ties Japan has started its own R&D projects starting from the desalination technology, and now various private industries and government ministries are actively engaging in R & D of membrane technologies in Japan. In Table 1 the chronological developments of important events of developments and projects relating membrane technologies inside and outside of Japan are introduced and their details will be explained. The first membrane technology applied in the Japanese industry was a electrodialysis(ED) process using ion-exchange membranes. These membranes were first developed in early 50ties and the Japanese government decided to use this method for concentration of sea-water to produce salt, which was then produced by solar evaporation. This development program started from 1960 by the Japan Monopoly Corp.(at that time). To apply ED process for sea-water concentration it was necessary to develop ion-exchange membranes having very low electric resistance to avoid energy loss due to Joule heat, and those having selectivity to permeate single valent ions only to avoid scale formation in the ED stacks. Three Japanese companies, Asahi Glass, Asahi Chemical and Tokuyama Soda, have succeeded to develop such membranes, and until 1971 all of the seven salt manufacturing companies had adopted ED for production of food salt.