Writers : Nakhaei, Malyhe; supervisor:M. H. Karimpour, Kh. Ebrahimi; advisor: A. Mazaheri
Refference : M.Sc. Thesis, Ferdowsi university, Mashhad
Publishing Year : 1381

Abstract :

Bentonite is a montrnorillonite clayey rock with having an enormous capacity for absorbing water, a high cation exchange capacity. swelling, plasticity. and binding power. This properties ensure the continued use of bentonit for various diverse applications. Na-bentonite is used in well drilling mud, iron pelletizing, foundry cores, moulds, arid civil engineering. Ca-bentonite is used in the refining of .vegetable and animal oil, animal feedstuffs. and petroleum refining. While organoclays is used in refining oil, fats, and solvents; gelling greases and paint .and producing carbonless copy paper In the province of Khorasan, Due to widespread acid to intermediate volcanism cluding Tertiary time provided suitable condition for major bentonite: deposition. 120 samples were taken from the following bentonite deposits، Gelkan, Grimong, kourghond, Chah-Taleb, Chah-Keshmire, Kuh Sefied Hesamie, Boroon, Eshkaftoo, and Boteh Zir. Based on field work, it is clear thai .all of these bentonite were ash fall deposited in alkaline lake ,Based on mineralogical and chemical analyses, bentonite from Gelkan .Hesamie, Chah Keshmir, Chah Taleb and kuh Sefied are Na-bentonite. Grimong .Eshkaftoo, and Boroon are Na-Ca bentonite and Boteh Zir and Kourghond are Ca bentonite. The montmorillonite content of Kourghond, Chah Kashmire, Chali Taleb, and Gnmong are the same and in the range of 45 to 55 percent. Boroon Deposit has the lowest montniorillonitc and is about 28 percent. The montmorillonite content of Eshkafatoo? is 45 to 93 Botech Zir is 51 to 79%and in Kuh Selied is between 49 to 76% , Quartz and cristobalit are the second important mineral. Halite, carbonate, and gypsum are found in some deposits. Test required for foundry use indicate that bentonite from Kuh Sefied Kourghond, Eshkafioo, and Botch Zir are suitable for foundry. Other bentonite deposits are not. Bentonite with less than 50 percent nlontmorillonite is not good for foundry.

Subject List : Bentonite