Tailoring sustainable pretreatment materials for reverse osmosis: Banana-peel carbon-TiO2/Te biocomposites as effective adsorbent

Abstract

This research delves into the challenges and prospects surrounding using low-cost pretreatment media, specifically organic waste in the form of banana peels, for reverse osmosis desalination. The banana peels are transformed into activated carbon (BPc) and combined with titanium dioxide embedded tellurium (TiO2/Te) to synergistically enhance the adsorption performance in the pretreatment stage of the reverse osmosis (RO) process. BPc-TiO2/Te composites have undergone thorough characterization showing the presence of bonding chemical groups such as O-H, C-C, CO, CC, C-O, Ti-O-Ti, and C-H bending vibrations. Morphological analysis demonstrated an evenly distributed arrangement of TiO2/Te particles on the BPc surface, with particle diameters ranging from 79.78 to 340 nm and an average diameter of 134 nm. Energy dispersive X-ray (EDX) characterization confirmed the presence of essential elements, including carbon (C), oxygen (O), titanium (Ti), and tellurium (Te), within the BPc-TiO2/Te composites. X-ray diffraction analysis (XRD) analysis showcased a well-defined crystalline pattern of BPc-TiO2/Te composites, predominantly exhibiting the anatase phase. The optimal seawater concentration for the most effective performance of the BPc-TiO2/Te adsorbent was found to be 5000 mg/L (5 ppt), with an optimal contact time of 90 min, resulting in an impressive adsorption capacity of 46.97 mg/g with adsorption percentage of 93.94%. Compared with several studies related to BPc, the modification BPc-TiO2/Te composites is a novel for seawater adsorption application. The combination of BPc with TiO2/Te presents novel opportunities to improve the modification of pretreatment media within the reverse osmosis process.