Rapemeal valorisation: improving the economics of biodiesel manufacture

Rapemeal protein has many potential functions in rubber compounding including a potential strengthening and stiffening (reinforcing) effect and an influence on the curing behaviour. The general approach in Loughborough's part of the project is to start with a broad scope of potential compounds in screening experiments, then narrow the range of compounds in an optimisation process and finally focus on a couple of compounds for pilot plant evaluation. Throughout the project, close collaboration between Loughborough University and Avon rubber is required to ensure applicability of lab scale experiments to the practical and commercial needs of industry and hence, maximise the potential for commercial exploitation of meal protein in rubber compounds. Screening experiments will be carried out with rapemeal protein added to unfilled and filled compounds. Two simple or model compounds will be used, one based on a non-polar rubber such as EPDM and the other based on a polar rubber such as NBR. This will allow evaluation of reinforcing effects of the protein on the rubber, and potential interactions with particulate fillers. For the screening experiments just limited physical tests (e.g. cure, tensile) will be carried out to determine a range of potential target applications for compounds. Results will also indicate what adjustments must be made to the compound formulation and processing conditions to improve properties. Further sets of experiments involving mixing, testing and analysis will be carried out to optimise compounds for the identified target applications. Optimisation may include changes to the formulation such as partial replacement of filler or rubber with protein, adjustment of the cure system and use of other additives, such as plasticisers. When formulations and mixing conditions have been optimised a fuller set of tests will be carried out, depending on the target applications identified and according to existing protocols and standards established by Avon. Following the optimising experiments larger scale mixing trials and associated testing will be planned to be carried out at Avon Rubber and the feasibility of scale-up to pilot plant level will be investigated.