Microfiltration ceramic membranes from Cameroonian in Allophane rich soils and husked rice: physico-mechanical, chemical characterization and application to the treatment of drinking water

The presence of particles in drinking water and their resistance to several disposal methods is a major problem in Cameroon. The work presented in this manuscript focused on the synthesis of a ceramic membrane based on allophane rich soils for effective microfiltration in the clarification of drinking water. This work focused on the assessment of the suitability of allophane rich soils and rice hulls for the domestic treatment of drinking water. Rice hulls from the city of Yagoua have been used as a blowing agent. Several formulations have been produced with different allophane and husk rice proportions (60-40, 70-30, 80-20 and 90-10%) and at a sintering temperature of 1200 °C. The originality of this membrane lies in its monolayer structure which is at the same time the support layer and the active layer for microfiltration. The filters were characterized, the filtration tests were carried out. Chemical analysis of the raw materials revealed a high level of essential minerals. The thermal analysis made it possible to stop the heat treatment at 1200°C. Textural analysis of the membranes revealed that the formulated membranes had pore volumes between 30 and 43%. These characteristics are consistent with microfiltration. SEM carried out on the surface and in cross section of the membranes revealed that the pores are uniformly distributed over the entire surface and interconnected in depth. The membranes have been subjected to good mechanical and chemical resistance. These membranes can therefore be used effectively for microfiltration assisted by transmembrane pressure. We obtain a minimum flow rate of 17.43 mL/hour and a final turbidity of 7.65 NTU. This value is close to the quality limits of drinking water according to the standard of the French government which fixes the turbidity of tap water less than or equal to 2 NTU while UNICEF fixes this standard at 5 NTU.