A preparation method of tripolyglycerol monostearate is to prepare by taking glycerol as a raw material:
The specific preparation steps are as follows:
(1) Glycerol polymerization: with alkali as catalyst, at about 260 ℃, under nitrogen protection, glycerol is condensed and dehydrated into triglycerol,
(2) Alcoholization of triglycerol: Using alkali as a catalyst, at about 230°C, under nitrogen protection, triglycerol is directly esterified with stearic acid.
In this preparation process, about 4% of the total amount of water will be generated (that is, the total output of the product will be reduced by about 4%), wherein the water needs to consume energy to remove (it has been removed during the chemical reaction process), In addition, stearic acid is more expensive, thus increasing the production cost. Some manufacturers also use hardened oil and triglycerol as raw materials to prepare tripolyglycerol monostearate, but they still cannot solve the problem of high cost.
Specific preparation method:
(1) Under the pressure of -0.09MPa, mix and heat glycerol and a compound mixed basic catalyst (a mixture of NaOH and NaH2PO2 with a mass ratio of 1:1) that accounts for 0.4% by weight of glycerol to 250° C. After concentrating and dehydrating, the trimerization is obtained. glycerin;
(2) under the pressure of -0.09MPaa, add 10mol tripolyglycerol and 0.1mol compound mixed alkaline catalyst (NaOH and NaH2PO2 mixture with a mass ratio of 1:1) into the reactor, mix evenly, and heat to 60°C;
(3) nitrogen is introduced into the reactor, 6mol of recovered tristearate is added to the tripolyglycerol and compound mixed basic catalyst mixture in step (2), the temperature is raised to 200°C and stirred, and the temperature is lowered after the esterification reaction for 6h, Cool to normal temperature to obtain solid tripolyglycerol monostearate.
During the whole reaction process, nitrogen needs to be replaced continuously.
Advantages of this method:
(1) this method solves the problem that the traditional old process production cost is high for many years, and this method provides the by-product ditriester and triglycerol that are produced when the reclaimed distillation monoglyceride manufacturer produces the distilled monoglyceride as raw materials to prepare trimer Glycerol monostearate, the price of the ditriester used is only about 57% of stearic acid and about 85.7% of hardened oil. This preparation method can effectively reduce the production cost of tripolyglycerol monostearate, The process is simple, the conditions are easy to control, and the high-quality tripolyglycerol monostearate can be industrially produced in large quantities.
(2) this method produces triglycerol monostearate by esterification reaction of triglycerol and ditriester (at high temperature, the method for preparing triglycerol monostearate, using alkali as catalyst, compared with the traditional process, produces about 4% less Water, thereby reducing production energy consumption, in line with the requirements of green environmental protection.
(3) In the reaction process of this method, nitrogen is used as the protective gas and the reducing agent NaH2PO2 or NaH2PO2·H2O in the compound mixed alkaline catalyst is used to effectively prevent the decomposition of saturated fatty acids and darkening of the color at high temperature, and reduce the peculiar smell and odor of the product. .
(4) Tripolyglycerol monostearate and propylene glycol monostearate prepared by this method are compounded to obtain an emulsified composition of this method, and the emulsified composition is applied in cakes, which can obviously improve the quality of cakes, increase the The volume of the cake makes the texture of the cake delicate and soft.
