###### Abstract
Given the difficulties inherent in its separation from reactional medium and maintaining its performance in photocatalytic processes, it is important to develop techniques for incorporating powders into supports. In this ambit, supports with high porosity, low density, and good mechanical resistance may have advantages in the absorption of light and catalyst immobilization [14; 19; 20]. Specific ceramic materials have shown promising characteristics in this sense, namely when they reveal high adsorption capacity, large pore volume, thermal stability, and good mechanical properties [21; 22]. In particular, the lightweight expanded clay aggregates (Leca(r)) present good characteristics to support fine particulate catalysts. Leca is a ceramic material produced by firing clay in high-temperature rotary kilns. It is recognized as a substrate of great interest due to its inherent mechanical strength, low density, and high porosity [23]. These characteristics may improve the mass transfer of the pollutant molecules through the catalyst and the absorption of light radiation [24]. Leca has been used in lightweight mortars and concretes, refractory mortars, piping protection, prefabrication of structures, agriculture, and floriculture. Therefore, Leca presents good characteristics to be used as a support of TiO\({}_{2}\) in the photocatalytic oxidation processes. Although few studies have considered Leca coating with TiO\({}_{2}\), it has already been identified as a good material for the degradation of several contaminants [25; 26; 27]. [PERSON] et al. [25] demonstrated that TiO\({}_{2}\) nanoparticles supported on Leca achieved high levels of ammonia removal in liquid effluents through photocatalysis. [PERSON] and [PERSON] [26] showed that Cu/TiO\({}_{2}\)/Leca reached good phenol degradation in synthetic wastewater. Some authors highlighted the advantage of TiO\({}_{2}\) coating of Leca due to its good adsorption properties, which promote photocatalytic activity [27]. [PERSON] et al. [28] coated TiO\({}_{2}\) on perlite light aggregates for water purification, confirming that the floating properties of these materials combined with TiO\({}_{2}\) can promote the use of sunlight in the purification of shallow water reservoirs and industrial waste stabilization ponds. [PERSON] et al. [29] developed a TiO\({}_{2}\) photocatalyst supported by perlite light aggregates for degradation of SMX in aqueous solutions and verified improvements in the photodegradation rate, achieving 60% of degradation. In the literature, several methods have been proposed for the TiO\({}_{2}\) immobilization onto ceramic materials, namely sol-gel, dip-coating, impregnation method, chemical vapor deposition, electrophoretic deposition, and electrochemical treatment [22; 25; 30]. These methods have demonstrated good efficiency in preparing catalysts for treating pollutants [31]. The impregnation method was selected in the present study since it is a simple and efficient technique to prepare supported catalysts for heterogeneous reactions. Therefore, the present study aims to develop a photocatalyst using TiO\({}_{2}\) P25 as a precursor on ceramic support (Leca) to be used in the oxidation of synthetic wastewater composed of water and SMX. The main variables of the impregnation method are evaluated in terms of TiO\({}_{2}\) immobilization yield. In particular, the load of TiO\({}_{2}\) on the suspension used for drowning the Leca is optimized, testing the photocatalytic activity over SMX in ultrapure water. The morphological characterization of the developed, supported catalysts is also considered.