Characterisation and Valorisation of the Moroccan Diatomite

Abstract

Morocco is known for the diversity of its natural resources. In particular, the mineral substances, diatomites, material relatively abundant but poorly exploited in Morocco. The aim of this work is to determine the geochemical and textural characteristics of the different diatomite deposits of north-eastern Morocco in order to compile a database with the different properties of these sediments. These data are valuable to guide the use and exploitation of this natural georesource. Samples from 3 deposits were characterised by different techniques of analysis: sedimentological (granulometry, calcimetry), chemical (pH, X-ray diffraction, infrared spectrometry and transmission electron microscopy coupled with EDX). We also performed thermogravimetric analysis of some samples. Results revealed that diatomite is a fine, moderately refractory material with a basic pH. While, the CaCo3 content varies between different deposits. It is composed mainly of silica and has a well-developed porosity. In addition, thermogravimetric analysis revealed a loss of mass with temperature increase. A moderate variation in the chemical composition of the diatomite was observed from one deposit to another. Generally, we can stipulate that the diatomite from the Rif deposit is relatively a good quality. It has relatively the same physico-chemical properties as the neighbouring regions.