Factorial design applied to sodium activation of a ...
MATERIALS AND METHODS. Materials: clay samples from Quatro Barras, Paraná, were used as bentonite source. This region has the largest Brazilian bentonite reserve (estimated as % of the total) and it is the least commercial exploited, accounting for only % of raw bentonite produced in Brazil 11.. Bentonite pretreatment and characterization: aqueous suspensions of .