Synthesis of superacid sulfated TiO2 nanowires for esterification of waste cooking oil

Cahya Fadilah, Cepi Kurniawan, Muhammad Ridwan, Muhammad Al Muttaqii, Egi Agustian, Agustina Sus Andreani, Adid Adep Dwiatmoko, Indri Yati

Research output: Contribution to journalArticlepeer-review


Sulfated TiO2 nanowires (STNW) were prepared by molten salt method from anatase TiO2 followed by sulfatation using ammonium sulfate precursor. The phases, morphologies, surface properties and acidity of the STNW were characterized using X-ray powder diffraction (XRD), scanning electron microscope-energy dispersive X-ray (SEM–EDX), nitrogen physisorption, and temperature-programmed desorption of ammonia (NH3-TPD), respectively. STNW has a rutile structure and shows a needle-like one-dimensional (1D) nanowires morphology with mean crystal size calculated from Scherrer equation was 53.35 nm. The catalytic activity of the as-prepared STNW for esterification of waste cooking oil (WCO) was performed in comparison to sulfated anatase TiO2 (STA). The STNW catalyst exhibited higher conversion and yield compared to STA. Moreover, the reaction rate of STNW catalyst was 1.3 times higher than STA although the total acidity of STNW catalyst was slightly lower than STA. The superior catalytic activity of STNW was corresponds to its higher temperature acid sites of STNW compared to STA, indicating a super acidity of the catalyst. The optimum reaction conditions of 3 h reaction time, 1:26 molar ratio of WCO to methanol, 3 wt% catalyst loading to WCO and 65 °C reaction temperature give the catalytic conversion of 99.5%. The result implies that STNW act as promising acidic heterogenous catalyst for the esterification of free fatty acids with good reusability. Graphical abstract: [Figure not available: see fulltext.].

Original languageEnglish
Pages (from-to)1529-1544
Number of pages16
JournalReaction Kinetics, Mechanisms and Catalysis
Issue number3
Publication statusAccepted/In press - 2023


  • Esterification
  • FAME
  • Heterogenous catalyst
  • Sulfated TiO nanowires


Dive into the research topics of 'Synthesis of superacid sulfated TiO2 nanowires for esterification of waste cooking oil'. Together they form a unique fingerprint.

Cite this