Study On The Preparation Of PEG Fatty Acid Ester From Crude Rice Bran Oil And The Application In Water Emulsion

As long as we know that China is an agriculture country and every year thepesticide usage amount nearly500–600thousand tons, more than one billion acres ofland exposed to the pesticide residues. Most of the pollution come from surfactantsused in the pesticide formulations, these unbiodegradable surfactants enter into soilwith the pesticide, which not only pollute the farmlands but also the surroundingenvironment. In recent years, with the growing awareness of protecting environment,research and develop the green environment friendly surfactant has become a hotsubject.China is the largest producer of rice, it owns abundant of rice bran resourcewhich is a kind of very important biomass resource. Rice bran is the byproduct ofwhite rice, it is a mixture of the rice skin, rice embryo and some broken rice. Thereare abundant of substances in rice bran, such as the oil, protein and moisture, and soon. Except these rich compositions, there are also some valuable substances, such assqualene, vitamin E and sterol, other active substances. The rice bran has a wide rangeof applications, it can be the nutritional rice bran oil after deep processing, and therice bran is the resource of biodiesel oil production via esterification andtrans-esterification process. The production of biodiesel oil can both ease the risk offossil energy and offer reference value to the renewable energy development. Theanother way of the rice bran is to develop green surfactant, as we know, there are lotsof free fatty acids in the crude rice bran oil, it can be kinds of green surfactants viaesterification, sulfonation reactions.In this paper, we chose the crude rice bran oil as the raw material to synthesizePEG fatty acid esters and evaluated properties of the obtained products. Thesurfactant under optimal synthesis conditions is used in the pesticide formulation, it turns out that the obtained O/W formulation has good stability.First of all, the second chapter of this paper use PEG600and pure oleic acid toprepare PEG600fatty acid ester and investigate the optimal conditions under differentmolar ratios: catalyst dosage is1.0wt%, reaction time is2.5h, the esterification ratehas no obviously change but the product’s colour turns shallow when the salad oil’sdosage is two times than the reaction raw material.And then, on the base of the second chapter, the third chapter use PEG600andcrude rice bran oil as raw materials to synthesize PEG600fatty acid ester, andinvestigate the reaction conditions under different molar ratios. The optimal conditionis that the catalyst dosage is1.0wt%, reaction time is3.0h. The optimal product isused to prepare water emulsion, and we also investigate the effects of differentprocess variables on emulsion stability. The optimal process conditions are: ratio ofPEG600fatty acid ester/Tween80,5:5, emulsifier dosage,6wt%, mass ratio ofoil/water phase,5:5, emulsifying time,13min, cosurfactant dosage,0.3wt%.Finally, in the fourth chapter, we use the free fatty acid in the crude rice bran oilas raw material to synthesize PEG400fatty acid ester, and investigate the optimalsynthesis conditions: molar ratio between PEG400and fatty acid is1:1, catalystdosage is0.5wt%, reaction temperature is100℃, reaction time is2.5h. We alsoinvestigate the product’s ability, it turns out that the product has good surface activity.The optimal product uses as emulsifier in the preparation of water emulsion, and weinvestigate the effects of different process variables on emulsion stability. The resultsis: ratio of PEG400fatty acid ester/Tween80,5:5, emulsifier dosage,6wt%, massratio of oil/water phase,3:7, emulsifying time,10min; cosurfactant dosage,0.3wt%.It also turns out that the prepared water emulsion under optimal conditions has goodstability.