Wastewater Treatment

Supported TiO2 in Ceramic Materials for the Photocatalytic Degradation of Contaminants of Emerging Concern in Liquid Effluents: A Review

“…In this sense, the development of technological processes that guarantee efficiency in the degradation of these compounds without the formation of dangerous intermediate products presents themselves as competitive solutions in the treatment of effluents. Therefore, the process of wastewater treatment with environmentally friendly methodologies and favorable cost-benefit has attracted the attention of several researchers [ 25 ]. The heterogeneous photocatalysis process has been highlighted due to its characteristics.…”

“…The sol-gel method is a process for synthesizing materials from a liquid solution of organometallic precursors [ 132 ]. Titanium (IV) butoxide, titanium isopropoxide, and titanium tetrachloride (TiCl 4 ), inorganic salts, are the precursors generally used for the synthesis of TiO 2 nanocomposites using the sol-gel method [ 25 , 107 ]. Among the precursors in the sol-gel method, titanium isopropoxide can be solubilized in alcohol, and in this solution, two simultaneous reactions occur, namely hydrolysis and condensation.…”

“…Among the precursors in the sol-gel method, titanium isopropoxide can be solubilized in alcohol, and in this solution, two simultaneous reactions occur, namely hydrolysis and condensation. In this case, hydrolysis is the main chemical reaction that leads to the transformation of precursors into oxide monomers, and condensation is responsible for grouping these monomers to form a chain [ 25 , 133 ]. Belet et al [ 134 ] compared two synthesis processes by the sol-gel method, aqueous synthesis, in which the reaction takes place in water, and organic synthesis, in which the reactions take place in an organic solvent and only a quantity of stoichiometric water is added to the reaction medium.…”

“…Moreover, the sol-gel method allows strong adhesion of the coating to the substrate and can be performed at ambient temperature [ 132 ]. Nevertheless, some disadvantages of the method concern the wide variation in particle size distribution and the need for a calcination step for crystallization, which can result in the melting of the substrate [ 25 , 107 ].…”

“…A steam deposition apparatus suitable for use in the film-forming process is required. According to [ 25 ] CVD synthesis method falls between two categories either, chemical or physical process.…”