Fabrication of TiO₂ Spheres and a Visible Light Active α-Fe₂O₃/TiO₂-Rutile/TiO₂-Anatase Heterogeneous Photocatalyst from Natural Ilmenite

Abstract

High-purity (98.8%, TiO 2 ) rutile nanoparticles were successfully synthesized using ilmenite sand as the initial titanium source. This novel synthesis method was cost-effective and straightforward due to the absence of the traditional gravity, magnetic, electrostatic separation, ball milling, and smelting processes. Synthesized TiO 2 nanoparticles were 99% pure. Also, highly corrosive environmentally hazardous acid leachate generated during the leaching process of ilmenite sand was effectively converted into a highly efficient visible light active photocatalyst. The prepared photocatalyst system consists of anatase-TiO 2 /rutile-TiO 2 /Fe 2 O 3 (TF-800), rutile-TiO 2 /Fe 2 TiO 5 (TFTO-800), and anatase-TiO 2 /Fe 3 O 4 (TF-450) nanocomposites, respectively. The pseudo-second-order adsorption rate of the TF-800 ternary nanocomposite was 0.126 g mg –1 min –1 in dark conditions, and a 0.044 min –1 visible light initial photodegradation rate was exhibited. The TFTO-800 binary nanocomposite adsorbed methylene blue (MB) following pseudo-second-order adsorption (0.224 g mg –1 min –1 ) in the dark, and the rate constant for photodegradation of MB in visible light was 0.006 min –1 . The prepared TF-450 nanocomposite did not display excellent adsorptive and photocatalytic performances throughout the experiment period. The synthesized TF-800 and TFTO-800 were able to degrade 93.1 and 49.8% of a 100 mL, 10 ppm MB dye solution within 180 min, respectively.

Fabrication of Naturally Derived Chitosan and Ilmenite Sand-Based TiO2/Fe2O3/Fe-N-Doped Graphitic Carbon Composite for Photocatalytic Degradation of Methylene Blue under Sunlight

“…The higher resolution spectrum of Fe 2p of the metal oxide product obtained from ilmenite, IL ( Figure 6 f), showed six peaks at 711.43, 714.04, 719.22, 724.91, 728.89 and 733.37 eV. They were assigned to Fe 2 O 3 , Fe-OH, satellite feature of 2p 3/2 , 2p 1/2 of Fe 3+ , 2p 1/2 of Fe 3+ in Fe-OH and satellite feature of 2p 1/2 , respectively [ 60 ]. The higher resolution spectra of Fe 2p of the composites ( Supplementary Figure S2o–r ) consist of an additional peak at 710.4 eV, which represents the presence of 2p 3/2 of Fe 3+ of Fe 3 C. The higher resolution spectrum of Ti 2p of the metal oxide product obtained from the ilmenite, IL ( Figure 6 g), showed four peaks at 458.19, 459, 464.16 and 471.53 eV, which were assigned to the 2p 3/2 Ti 4+ of TiO 2 , 2p 3/2 Ti 4+ of Fe 2 TiO 5 , 2p 1/2 of Ti 4+ and to the satellite peak, respectively [ 61 ].…”

“…of Fe 3+ in Fe-OH and satellite feature of 2p 1/2 , respectively [60]. The higher resolution spectra of Fe 2p of the composites (Supplementary Figure S2o-r) consist of an additional peak at 710.4 eV, which represents the presence of 2p 3/2 of Fe 3+ of Fe3C.…”

Kinetics and Thermodynamics Study of Methylene Blue Adsorption to Sucrose- and Urea-Derived Nitrogen-Enriched, Hierarchically Porous Carbon Activated by KOH and H3PO4

“… 6 Hence, it is vital to remove dyes from water reservoirs. There are many methods available for such purposes including membrane filtration, 7 nanofiltration, 8 adsorption, 9 remediation by microorganisms, 10 ion exchange, 10 ozonation, 11 photooxidation, 12 − 14 chemical reduction, 15 etc. These methods possess disadvantages such as sludge production, use of expensive chemicals, poor efficiency, short half-life, formation of byproducts, regeneration difficulties, 16 etc.…”

Visible Light Active Silver Decorated Iron Titanate/Titanium Dioxide Nanohybrid for Sterilization of Explants Grown by In Vitro Technique

“…[ 21 ] Traditionally, FeTiO 3 used in catalysis applications has been synthesized from TiO 2 which is extracted from natural minerals and few attempts have been made to use the modified naturally occurring ilmenite as a visible light active photocatalytic material. [ 22–26 ]…”

“…[21] Traditionally, FeTiO 3 used in catalysis applications has been synthesized from TiO 2 which is extracted from natural minerals and few attempts have been made to use the modified naturally occurring ilmenite as a visible light active photocatalytic material. [22][23][24][25][26] The present study describes a method to synthesize Ag decorated FeTiO 3 /TiO 2 nanohybrid derived from natural ilmenite as the precursor material and its application in photo-sterilization of plant tissues (plant nodes). Ag-FeTiO 3 /TiO 2 nanohybrid was derived from Sri Lankan ilmenite (beach sand) and utilized in the VL region to eliminate plant exophytic pathogens.…”