A New Composite Based on Gellan Gum/Chitosan and Hydroxyapatite Contains Gallium for Removing the Anionic Dyes Remazol Blue and Remazol Red

The textile industry's waste is a primary pollutant in aquatic environments. One of the alternatives for pollutant removal is the adsorption process. Among them, polysaccharides have numerous advantages regarding their use: they are non-toxic, abundant in nature, biodegradable, hydrophilic, and have several other properties. The study aimed to investigate new composite materials with morphology based on chitosan and gallium-doped hydroxyapatite (HAp) to remove remazol blue and remazol red dyes in an aqueous solution. In order to have a better understanding of the sorption process, different techniques were used to characterize the composite. Regarding the crystallinity, gallium's presence did not affect HAp's crystalline structure. On the other hand, the FT-IR and TG spectra of the composite indicate interactions between the precursor materials in producing the same by shifting the characteristic bands and increasing thermal stability. The morphological analysis by FESEM and Tomography presented essential characteristics for applying the composite in the adsorptive process through the pores formed in the material. Open and interconnected pores were observed with average diameters of 20 & mu;m on the upper and lateral face surface and 95 & mu;m on the inside. A more significant number of pores were observed inside, thus influencing the adsorption. In addition, with the EDS, it was possible to observe the presence of precursor elements for forming the composite. It is concluded that the composite was successful and showed excellent potential for removing Remazol Blue RGB and Remazol Red with adsorption of 341.41 & PLUSMN; 6.82 and 584.89 & PLUSMN; 23.39 mg/g, respectively.