Hydrophobic TiO2‐SiO2 Aerogel Composites for Fast Removal of Organic Pollutants. Issue 37 (7th October 2018)

• Record Type: Journal Article
• Authors: Xu, Haixun; Jia, Jiajia; Zhao, Shanyu; Chen, Peixin; Xia, Qun; Wu, Junyong; Zhu, Pinghua
• Is Part Of: ChemistrySelect. Volume 3:Issue 37(2018)
• Page Start: 10483
• Page End: 10490
• Publication Date: 2018-10-07
• Subjects: aerogel -- co-solvent -- hydrophobic -- optimization -- photocatalysis; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201801646
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: SiO2 ‐TiO2 aerogel composites were synthesized by co‐gelation of a titanium tetrachloride in an aqueous silicic acid solution. As‐prepared hydrogels were hydrophobized by trimethylchlorosilane and then dried at 150 °C and ambient pressure condition. The resulting gel composites are typical 'pearl‐necklace' aggregate silica structure which is intertwined at the nanometer level with titania, yielding a three‐dimensional hydrophobic SiO2 ‐TiO2 interpenetrating network with an improved pore structure, BET surface area, and photocatalytic performance when compared to their calcined hydrophilic gels. A hydrophobic aerogel composite which is optimized in an L9 (3 4 ) orthogonal array features a fast removal (<30 mins) of organic compounds (> 89% removal of methyl orange and humic acid) in a 10 mg/L solution under UV light exposure, in which ethanol‐water was used as co‐solvent. In comparison, the calcined hydrophilic xerogel shows 10‐fold longer degradation time (∼ 300 mins) to remove the same concentration waste from the water streams. Abstract : A high and fast degradation for organic pollutants is reached by using hydrophobic aerogel composites with assistance of organic co‐solvent to eliminate the interface between gel surface and pollutant solution.