Simple and Reliable Quantification of Kaolinite in Clay Using an Oven and a Balance

Abstract

This study investigates the feasibility of using an oven and a balance to determine the kaolinite content in clay. The mass of 14 clays was recorded after three heating steps at 200 ℃, 400 ℃, and 600 ℃. The two upper temperatures permit to accurately consider the kaolinite dehydroxylation, whereas the step at 200 ℃ considers the moisture state of the clay. The protocol of the test was optimized with an adequate sample mass of 10 g and finer than 4 mm. The correlation with thermogravimetric analyses (TGA) results shows a very high correlation coefficient (R2 = 0.99). Since TGA is not available in all laboratories, this alternative method permits to characterize the clay without any expensive equipment.