In recent years, there have been numerous studies based on the removal of heavy metal ions from aqueous solutions\r\nusing lignocellulosic materials, which are capable of adsorbing various pollutants at low concentrations. Rice husks\r\nconstitute a biomass waste that has found multiple applications in different fields, such as the removal of heavy metals.\r\nAfter this treatment, a biomass-contaminant waste is generated, which currently does not have viable and low cost\r\nalternatives for its final disposal. Consequently, the objective of this work is to evaluate the feasibility of incorporating\r\nthe rice husk-contaminant residue in ceramic matrices to immobilize the heavy metals cadmium and lead contained in\r\nthese materials. Figure 1 shows the microstructure of natural rice husks, rice husks activated with H3PO4 + Cd and rice\r\nhusks activated with KOH + Pb, obtained by SEM. The ceramic pieces were obtained by uniaxial pressure at 25MPa of\r\ncommercial clay-rice husks mixtures with and without adsorbed metal, added in 10% in volume, heat treated at 1000°C\r\nfollowing firing curves similar to those used by the ceramics industry. The obtained products were characterized with\r\ndifferent techniques: porosity, modulus of rupture, permanent volumetric variation and loss of ignition, among others,\r\ntending to determine the properties of the obtained materials. In order to determine the immobilization of the heavy\r\nmetals in the clayey matrix, the ecotoxicity test was carried out on the samples, according to standard IRAM 29114\r\n(Argentina). From the general results, it can be concluded that the obtained ceramic pieces have immobilized within\r\ntheir structure the heavy metals contained in the added rice husks, and the obtained products present homogeneous\r\ntonality, defined edges, good degree of sintering and properties suitable to its use in service.
