Synthesis, characterization of SiO2 supported-industrial phosphoric acid catalyst for hydrolysis of NaBH4 solution. (2nd December 2018)

• Record Type: Journal Article
• Authors: Elghniji, Kais; Virlan, Constantin; Elaloui, Elimame; Pui, Aurel
• Is Part Of: Phosphorus, sulfur, and silicon and the related elements. Volume 193:Number 12(2018)
• Page Start: 806
• Page End: 821
• Publication Date: 2018-12-02
• Subjects: H3PO4 -- SiO2 -- catalyst -- sodium borohydride; Sulfur compounds -- Periodicals; Organosulfur compounds -- Periodicals; Phosphorus compounds -- Periodicals; Organophosphorus compounds -- Periodicals; Silicon compounds -- Periodicals; Organosilicon compounds -- Periodicals; 546
• DOI: 10.1080/10426507.2018.1515946
• Languages: English
• ISSNs: 1042-6507

Abstract

Abstract: Tunisian industrial phosphoric acid H3 PO4 was supported on silica gel SiO2 (SIPA) to catalyze the hydrolysis reaction of aqueous alkaline sodium borohydride (NaBH4 ). The SiO2 was produced from purified quartz sand using alkali fusion-acidification chemical process. The BET surface area results indicate that the prepared silica gel could reach a specific surface area up to 585 m 2 /g. The addition of PO3 H2 functional groups resulted in an increase of surface acidity of SiO2 catalyst as shown by FT-IR and DTA-DTG spectra. The total acidity of SIPA catalyst was determined by titration to be 2.8 mmol H + /g. SEM/EDS maps reveal the distribution of heavy metals on the silica surface. The effect of supported PO3 H2 functional groups and heavy metals on the NaBH4 hydrolysis reaction was studied for different ratios of SIPA catalyst to NaBH4 . The sample 12SIPA/NaBH4 leads to a very high hydrogen generation rate (up to 90%). The activation energy of hydrogen generation by NaBH4 hydrolysis was 25.7 kJ mol −1 . GRAPHICAL ABSTRACT: