Studying to use volcanic ashes and felsic volcanic rocks in Vietnam teritory as the treatment materials for environment pollution – preliminary results

The felsic volcanic rocks and tuff aged from Late Mesozoic to Kainozoic occur in many places in Viet Nam Territory, such as Tu Le area (in Northwest Region), Binh Gia area, Binh Lieu area (Northest Reigion), Nha Trang area, Dalat area (Central Region). The mafic volcanic ashes aged from Late Neogen to Quarternary distribute in central part of Vietnam such ash Con Co Island, Van Hoa High land. The samples of the tuff rock of Don Duong Stratum collected from field trip in Da Lat area have been treated (burned) at 650oC, 750oC, 900oC. The experimental results show that these materials, after treatment (heating in funace at the temperature 650oC, 750oC and 900oC) expressed absortion capacity up to 90% of selected organic matters (MO, MD) and heavy Metal (Pb2+) in the testing solutions. Among them, the sample heating at 900oC is the best material for Pb2+ absorption. The preliminary results show that the volcalnic felsic rocks and volcanic ashes in Viet Nam, after suitable treatments, can be used as an enviroment treatment materials.