Synthesis of sodium titanate catalysts using a factorial design for biodiesel production

Abstract

In this work, the synthesis of sodium titanate for the biodiesel production was evaluated with emphasis on the synthesis parameters of titanates in the conversion of vegetable oil to biodiesel. Sodium titanate catalysts were synthesized via sol–gel hydrothermal method and tested as heterogeneous catalysts for biodiesel production, using a factorial design 2k. Four experimental factors were considered: NaOH concentration, hydrothermal temperature, TiO2/NaOH ratio, and calcination temperature, using as response variable the catalysts activity in soybean oil conversion to biodiesel. Titanates were characterized by XRD, SEM, and N2 physisorption techniques. The presence of tri and hexatitanate were confirmed. Trititanate was the most efficient in the conversion of soybean oil to biodiesel, achieving around 80% with an alcohol:oil molar ratio of 6:1 at 55°C for 5 hr and 300 rpm. Among the trititanate catalysts, the best performing sample showed a surface area of 217 m2/g with a porous size average of 4.8 nm related to nanotube structure with inter and intra particle mesoporosity. Conditions to prepare the efficient performing catalyst were as follows: NaOH concentration, 7.5 M; hydrothermal temperature, 130°C; TiO2/NaOH ratio, 0.06 g/mL; and calcination temperature, 600°C.

Developments in Titanium‐Based Alkali and Alkaline Earth Metal Oxide Catalysts for Sustainable Biodiesel Production: A Review

“…The same group carried out a similar work [142] with a series of K‐containing nanotubular sodium tri‐titanate by varying the K : Na molar ratios of 0.11, 0.25, 0.34. The sample with 3.2 wt% of K showed a better conversion (96.2 %) of soybean oil to FAME at 1 h. Interestingly, Machorro, et al [143] . made a factorial design to obtain ideal conditions for the production of FAME from vegetable oil using sodium titanate as a catalyst.…”

“…The same group carried out a similar work [142] with a series of K-containing nanotubular sodium tri-titanate by varying the K : Na molar ratios of 0.11, 0.25, 0.34. The sample with 3.2 wt% of K showed a better conversion (96.2 %) of soybean oil to FAME at 1 h. Interestingly, Machorro, et al [143] made a factorial design to obtain ideal conditions for the production of FAME from vegetable oil using sodium titanate as a catalyst. In this process, instead of using high concentration of NaOH (10 M) as mentioned in the earlier studies, they achieved the higher catalytic activity using 7.5 M of NaOH that showed ~69.05 % of conversion of soybean oil to FAME.…”

Titanate Nanotubes-Based Heterogeneous Catalyst for Efficient Production of Biomass Derived Chemicals

“…Furthermore, the transesterification reaction kinetics followed a pseudo-first-order kinetics model. Simiarlly, the sodium titanate catalysts were prepared by sol–gel hydrothermal method, and the synthesis parameters of sodium titanates on the catalysts activity in soybean oil conversion to biodiesel were discussed using a factorial design ( Machorro López et al, 2021 ). Combing the characterization results and catalytic results, the authors pointed out that trititanate was the most efficient in the conversion of soybean oil to biodiesel, achieving around 80% conversion.…”

Sodium Titanate Synthesis For The Photocatalytic Degradation of NO

“…Other modi cations involve doping with noble metals to degrade organic matter (El Rouby et al, 2017). Their morphology is appropriate to increase the catalytic and photocatalytic activity due to tubular structure and surface areas > 200 m 2 /g (Machorro López et al, 2021). Then, the use of ST in the degradation of NOx is a potential option for NOx photo-reduction with the subsequent generation of N 2…”