“From seed to product” – Synthesis of high-value bio-polyol raw materials from white mustard seed processing and assessment of the influence of the degree of oxidation on the properties of the obtained products

The article discusses a method for the synthesis of plant-based bio-polyols in which the initial raw material was white mustard ( Sinapis alba ) seeds. The presented method included the process of pressing white mustard seeds to obtain unrefined oil and pressing-cake. The pressing process was optimized experimentally in order to obtain the largest possible amount of oil. The obtained oil was subjected to the process of sedimentation of seed residues and then subjected to tests such as determining the iodine value, density, viscosity and FTIR. In the next stage, the process of epoxidation of double bonds contained in mustard oil was carried out using a hydrogen peroxide solution in an equimolar amount, in a 1.5-fold excess and a 2-fold excess. The obtained epoxidized oils were purified and subjected to analytical and spectroscopic tests. In the third stage, the reaction of opening epoxy rings was carried out using 2,2′-thiodiethanol in equimolar quantities to the number of epoxy groups in each epoxidized oil. The obtained products were thoroughly characterized in terms of physicochemical properties such as density, viscosity, hydroxyl number, acid number, molecular weight and amount of individual elements (C, H, O and S). Bio-polyols were also subjected to FTIR and NMR studies. It was found that the presented "from seed to product" method allows for efficient and clean synthesis of full-value polyol raw materials in a single technological line. • Cold pressing of oil allows to obtain a valuable product for chemical synthesis. • Efficiency of obtaining oil from seeds depends on seed hardness and head pressure. • Technology enables production of bio-polyols from seeds in one technological line.