Honored with the Heisei Fifteenth Year Academic Prize from the Society of Sea Water Science,Japan

摘要

The author is deeply grateful for the academic prize awarded from the society of sea water science,Japan.This report is the summary of plenary lecture prescented for the prize.During investigation of some hydroxyapatites[Ca_10(PO_4)_6(OH)_2:HAp-Ca_10(PO_4)_4.2(SiO_4)_1.7(OH)_6.SiAp],the author discovered that "Lattice Ca~2+ ions"of the apatites were selectively ion-exchanged for such notorius cations as Pb~2+ or Cd~2+ ions in aqueous solution at room temperature and such interesting ion-exchangers were named as "Lattice Ion Ion-exchange"by the author.Thus,to selectively separate and uptake small amounts of K~+ ions from seawater in the presence of a large amount of Na~+ ions,K~+ ion memorizing lattice ion ionexchangers have been investigated and Na~+ form taeniolite(Na~+Mg_2LiSi_4O_10.2H_2O:Na~+T)was found to be a promising inorganic ion-exchanger.Lattice Na~+ ions of the Na~+T were highly selectively ion-exchanged for K~+ ions in dehydrated state from seawater.Further,SiAp and its extented inorganic ion-exchangers such as hydrotalcite and calcium hydroxide were found to have disinfection effect for Ecoli cells in wastewater.The author hopes that the above inorganic ion-exchangers will be extended to be key materials in evironomental and water 21st century.