Attapulgite Clay and Its Application in Radionuclide Treatment: A Review

Abstract

This article mainly describes the chemical and crystal structure of attapulgite as its unique crystal structure possess special physicochemical properties such as large specific surface area, adsorption performance, and cation exchangeability. By modification of attapulgite, such as purification, high temperature roasting and other physical modification or acid–base salt modification, organic modification, surfactant modification and other chemical modification can further improve its physicochemical properties. In this article, the modification methods of two aspects of physical modification and chemical modification are summarized, at the same time, the research progress and achievements of many scholars in attapulgite modification are reviewed. Through modified attapulgite the number of pores increased, channel become loose, pore diameter increases, pore volume increases, interlayer spacing increases, specific surface area increases, chargeability and adsorption activity change, and the adsorption performance of attapulgite is greatly improved. Many scholars have applied modified attapulgite to the treatment of radionuclides, and achieved remarkable results. It has been found that modified attapulgite has U(VI), Eu(III), Cs(III), Th(IV), both Eu(III) and Sr(II) have good adsorption properties, and the adsorption rate and adsorption capacity are greatly improved compared with the original soil. Based on the Summary of the attapulgite modification method and its application in the treatment of radionuclide, some suggestions on the research and application of attapulgite modification and the possible key research directions in the future are further proposed.