Obtenção de mulita e cordierita sintéticas a partir de argilas esmectíticas do distrito de Boa Vista-PB e soluções concentradas de sais.

Abstract

This work report a study on production of sintetic mulite and cordierite from smectite clays and concentrated salt solutions. Five smectite clays samples, having different colours, from Boa Mista - PB were used. Firstly, the clays were treated with aluminum sulfate and with aluminum sulfate and magnesium sulfate. Then they were calcinated at 1000-1300°C during 1h and/or 3h. The products were characterized by chemical analyse, determination of specific surface and real specific mass, thermogravimetric analyse, diferential scanning calorimeter. X-ray Aaalyse, scanning eletronic Microscope and refractoriness testing. The results has shown that both mulite and cordierite can be produced, and their purity depend of the clays chemical composition, calcination temperature and calcination time. Mulite was produced as unique phase at lowest calcination temperature from the dark-green colour clay. Although in all samples the Fe303 was present, cordierite was produced at lowest calcination temperature and with nearest theorical chemical composition from the chocolate colour clays.