Removal of Carbamazepine from Water by a Novel TiO₂–Coconut Shell Powder/UV Process: Composite Preparation and Photocatalytic Activity

Abstract

A novel TiO-coconut shell powder (TCNSP) composite, prepared by the controlled sol-gel method with a subsequent heat treatment, was investigated as an innovative photocatalytic absorbent for the removal of carbamazepine (CBZ). CBZ is used worldwide as an antiepileptic drug, which has recently been recognized as an important organic pollutant increasingly found in wastewaters from urban areas and other aquatic environments. The granulation process was performed by using a semiautomated mass production line to produce sufficient quantities of TCNSP composites, possessing sufficient crush strength for commercialization. Physical properties of the TCNSP composite such as crystallinity, morphology, crush strength, and the Brunauer-Emmett-Teller (BET)-specific surface area were controlled by the mass ratio of titanium dioxide sol and coconut shell powder (CNSP). Calcination at 700°C produced anatase phase TiO in the TCNSP composites with a BET high surface area of 454 m/g. Anatase crystallite size of the TCNSP composite increased from 2.37 to 15.11 nm with increasing calcination temperature from 500°C to 800°C. Calcinated TCNSP composites had higher CBZ removal efficiency (98%) than pure TiO (23%) and CNSP (34%) within a 40-min reaction time. Optimization of this innovative adsorption/photocatalytic process was obtained by a response surface methodology and a central composite design model, which indicated that this novel and sustainable technology was successful in removing CBZ from a solution.

Studies on the titanium dioxide nanoparticles: biosynthesis, applications and remediation

“…Composites of TiO 2 with coconut shell powder were prepared using sol-gel method with heat treatment. These composites were reported to remove 98% carbamazepine, antiepileptic drug which is an important organic pollutant [40].…”

Synergistic Removal of Humic Acid in Water by Coupling Adsorption and Photocatalytic Degradation Using TiO2/Coconut Shell Powder Composite

“…Conventional treatment processes (i.e., coagulationflocculation, membrane filtration, adsorption, and oxidation) have been widely applied to remove HA in water [3,5,6]. Among various types of treatment processes, heterogeneous photocatalysis using suspended TiO 2 or ZnO particles gained increased attention owing to the potential to degrade recalcitrant organic contaminants in water into nontoxic compounds using highly reactive transitory species , and singlet oxygen ( 1 O 2 )) [6][7][8][9][10]. In addition, TiO 2 and ZnO photocatalysts are nontoxic and chemically stable over a wide pH range [6][7][8][9][10].…”

“…Among various types of treatment processes, heterogeneous photocatalysis using suspended TiO 2 or ZnO particles gained increased attention owing to the potential to degrade recalcitrant organic contaminants in water into nontoxic compounds using highly reactive transitory species , and singlet oxygen ( 1 O 2 )) [6][7][8][9][10]. In addition, TiO 2 and ZnO photocatalysts are nontoxic and chemically stable over a wide pH range [6][7][8][9][10]. Although these nanoscale photocatalysts have great efficiencies in removing recalcitrant organic contaminants, the use of these nanoscale photocatalysts for commercial or industrial applications would require further processes such as separation and recovery.…”

“…Thus, numerous studies to immobilize these finely powdered photocatalysts on various supports (i.e., activated carbon, charcoal, clay, glass beads, membranes, polymer films, etc.) have been performed [4][5][6][7][8][9][10][11]. However, several inherent drawbacks resulting directly from the photocatalyst immobilization (i.e., low exposed surface area, mass transfer limitation, and low UV light transmission) still have been reported [8].…”

“…have been performed [4][5][6][7][8][9][10][11]. However, several inherent drawbacks resulting directly from the photocatalyst immobilization (i.e., low exposed surface area, mass transfer limitation, and low UV light transmission) still have been reported [8]. Although most drawbacks stemmed from the immobilization techniques between photocatalyst and support, the drawbacks from the photocatalytic system can be overcome through the optimization of the photocatalytic systems via response surface analysis.…”