Hydrodesulphurization (HDS), deuteriodesulphurisation, calcium hydrogenation and deuterium treatment are reactions that occur simultaneously when oil shales are treated with hydrogen. In this work, quantitative monitoring of the target elements (sulphur, calcium and magnesium) was carried out using the dispersive X-ray diffraction technique (a technique coupled with a scanning electron microscope). The treatment of oil shale with hydrogen with the objective, either to improve the products preventing oil shale (gas, oil and solid fuel) or in the particular sense to get rid of some undesirable elements having harmful effects on the course of the exploitations of materials we quote the phenomenon of corrosion. An example of this is hydrodesulphurization, which is a reaction that is used to remove sulphur. This hydrogenation reaction was followed in a first work for the different oil shale layers of Tarfaya (M. Hafid and A.Attaoui: 2022) at a temperature of 550°C. However we were able to raise the temperature to 750°C for this study, in the same sense of the continuity of the action by hydrogen on elements such as calcium and magnesium in the temperature domains this study has been continued.