Science-Hub - World of Science
A solid catalyst developed by a multidisciplinary team of researchers (GB) could enable farmers to produce biodiesel from any variety of vegetable oil in one step in the future.
Indeed, the production method used requires a number of steps that can neutralize and eliminate fatty acids contained in oil. Note that it is essential to remove these fatty acids that can corrode the engine parts for vehicles.
This project, funded by the Research Council Engineering and Physical Sciences Research Council (EPSRC, Research Council for Physical Sciences and Engineering) will bring together the universities of York, Manchester and Newcastle. The BP Biofuels is also a partner in this project. For now the researchers are still at the design phase of the catalyst.
According to Dr. Adam Lee from the Faculty of Chemistry at the University of York, biofuel producers are too heavily on the synthetic chemistry. Indeed, large quantities of chemical catalysts such as sodium hydroxide are used to accelerate the esterification reaction in which it is reacting the alcohol and oil for biofuel. That is why the researchers involved in this project aims to develop an innovative solid catalyst. This catalyst will be used in continuous flow reactors rather than batch reactors widely used in the production of biodiesel, but have many drawbacks. For example, with a batch reactor, it is difficult to separate the products of the reaction until it is complete. It is therefore impossible to produce ethanol on an ongoing basis.
To do this, researchers are trying to develop catalysts mesostructures solid second-generation high exchange surface. The interconnection between the pores of the catalytic surface will be defined by computer modeling. This technique allows to obtain catalysts whose geometry facilitates the chemisorption of the reactive phase fluid (vegetable oil). The catalyst used is silica type with a diameter of large pores to allow diffusion of long chains of molecules involved in the reaction. Silica was chosen as a substrate for its chemical properties, thermodynamic and structural properties. The catalyst will be tested in Newcastle in a continuous oscillatory flow reactor.
This catalyst can maintain chemical reactions: one to neutralize the free fatty acids while the other provides the esterification of triglycerides of vegetable oil into biodiesel. Acids will be converted into esters, non-corrosive molecules for vehicle engines. One solution would be to set up two beds of catalysts. On the first, the fluid flow would cope with fatty acids, before proceeding to the second bed for the creation of biodiesel. But ideally, researchers hope to develop catalysts which possess both acidic and basic sites, so that the acid sites estérifient contaminants reactions and basic sites in the production of biodiesel. For this, the researchers propose to graft on silica nanoparticles of magnesium oxide (solid) and a range of solid acids such as zirconium sulfate.
One of the objectives of the project is to obtain a catalyst suitable for raw materials such as Jatropha (shrub native to South America producing oil properties similar to those of diesel) which grows in arid and whose method of cultivation does not compete with food crops. Another objective of the research team is to make mobile reactors for the production of biofuels. Thanks to solid catalysts, it would be possible to create a reactor 2m long low weight (weight of the catalytic bed), in which vegetable oils would be paid to the summit and biodiesel would be collected at the base.