Optimising the biodiesel production process: Implementation of glycerol derivatives into biofuel formulations and their potential to form hydrofuels. (15th March 2020)

• Record Type: Journal Article
• Authors: Brock, Damian; Koder, Alexander; Rabl, Hans-Peter; Touraud, Didier; Kunz, Werner
• Is Part Of: Fuel. Volume 264(2020)
• Publication Date: 2020-03-15
• Subjects: Biofuel -- Drop-in fuel -- Vegetable oil -- Biodiesel -- Glycerol; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2019.116695
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Completely bio-sourced fuels including vegetable oils and derivatised glycerol. Direct applicability in unmodified up-to-date diesel engines. Significant optimisation of the biodiesel production process. Contributions to biofuels, drop-in fuels and hydrofuels possible. Abstract: A new biofuel concept is developed, enabling the usage of vegetable oils and glycerol derivatives in mixtures with biodiesel. This concept significantly enhances the biodiesel production's profitability and thus strongly contributes to the sustainability of future biofuels. After simple addition reactions with building block chemicals, less hydrophilic glycerol derivatives are obtained, which are compatible with biofuels. Even more, the products of the reactions of glycerol with acetone or butyric acid, referred to as solketal and tributyrin, respectively, lead to promising biofuels in mixtures with rapeseed oil and its biodiesel. Due to their low freezing points, they act as cloud and freezing point depressants, when added to vegetable oil/biodiesel blends. Further, since their viscosity is close to common biodiesel, biofuels containing high amounts of vegetable oil and even more glycerol derivatives than they arise during the biodiesel production can be obtained. Thus, this new class of biofuels enables adaptable compositions depending on the application and also the usage as drop-in fuel without any or just few percent of further additives. After optimising the formulations, ignition delay, exhaust gas recirculation, fuel consumption and combustion process measurements were performed in an unmodified upto-date diesel engine. The experiments showed that the properties of the formulated biofuels are either similar to or even better than diesel. The hydrotropy of the glycerol derivatives in these mixtures enables the potential to implement water into biofuels, so-called hydrofuels, reducing nitrogen oxide emissions and leading to further optimised dropin fuels.