Valorization of waste “date seeds” bio-glycerol for synthesizing oxidative green fuel additive

Bio-glycerol is a polar triol with a high boiling point and obtained as a by-product from transesterification of plant based oils. In this study, a fuel additive (Solketal, 2,2-dimethyl-1,3-dioxolane-4-methanol) was synthesized from the condensation of bio-glycerol with acetone in the presence of different tailored forms of beta zeolite. The bio-glycerol was obtained from the transesterification of waste “date seed” oil. Beta zeolite catalysts treated with acids (hydrochloric acid, nitric acid and oxalic acid) exhibited enhanced catalytic activity, irrespective of the nature of the acid used for the dealumination. Modified beta zeolite was characterized using the following techniques: X-Ray Diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, Energy Dispersive Spectroscopy, Ammonia Temperature Programmed Desorption and Brunauer Emmett and Teller analysis. The nitric-acid-treated beta zeolite sample exhibited a higher conversion than the other acid-treated samples. At optimum conditions, the bio-glycerol conversion and solketal yield were 94.26% and 94.21 wt%, respectively. The best catalyst formulation was reusable without any significant loss in its activity. The process described in this study offers an attractive route for converting bio-glycerol to green fuel additive (solketal), which has a wide range of commercial applications.