| In this paper refined camphor tree seed oil was prepared through degumming, decolorizing from camphor tree seed oil that directly pressed. Choose acidic ionic liquid as catalyst, the 1-decanoyl-rac-glycerol and glycerol monolaurate prepared by esterification method, esterification and transesterification continuously method, esterification and transesterification step by step method. Then analyze its structure, physicochemical properties and emulsifying properties by infrared spectrometry and national standard.Camphor tree seed oil degumming process were as follows:hydrated degununing with phosphoric acid, amount of phosphoric acid 3% (oil weight), amount of water 6%(oil weight), degumming time 40min, temperature 70℃, phospholipids content decrease from 9.5mg/g down to 1.1mg/g on this conditions. Decolorizing process were as follows:in the 20mmHg vacuum, vacuum decolorizing use mixed activated carbon and clay, the mass ratio activated carbon to clay 1:6 and amount was 5% (oil weigh), decolorizing temperature 100℃, time 40min, camphor tree seed oil decolorization rate was 86.5%, camphor tree seed oil became light yellow color from purple-blank.The physical and chemical index of refined camphor tree seed oil were: phospholipids 1.4mg/g, acid value 12.6mgKOH/g, iodine value 3.5gI2/100g, saponification value 287.8 mgKOH/g, density 0.186g/cm3, melting point 20-22℃average molecular weight 624.5. By gas chromatography analysis, camphor tree seed oil was mainly composed capric acid and lauric acid and the contents were 54.09% and 39.62%.Preparation of ionic liquid catalyst use three types that N-methylimidazole hydrogen sulfate salt ([Hmim]+[HSO4]-), 1-methyl-3-(3-sulfo-propyl) imidazolium hydrogen sulfate salt ([HSO3-pmim]+[HSO4]-) and 1-methyl-3-(3-sulfo-propyl) imidazole-toluene sulfonate([HSO3-pmim]+[pTSA]-). The properties of ionic liquid catalyst that:the transformation of camphor tree seed oil preparation of 1-decanoyl-rac-glycerol and glycerol monolaurate, use 1-methyl-3-(3-sulfo-propyl) imidazolium hydrogen sulfate salt as the esterification catalyst, 1-methyl-3-(3-sulfo-propyl) imidazole-toluene sulfonate as esterification transesterification continuously catalyst.Esterification reaction of camphor tree seed oil fatty acid that prepare monoglycerides use ionic liquid catalyst 1-methyl-3-(3-sulfo-propyl) imidazolium hydrogen sulfate salt, the optimal reaction conditions were:reaction temperature 150℃, amount of catalyst 3% (fatty acid weight), and molar ratio glycerol to camphor tree seed fatty acid 3:1, reaction time 2.0h, in this condition monoglycerides yield was 73.1%. Even if the acid ionic liquid was reused five times, the conversion of catalytic activity did not decrease obviously.Esterification and transesterification reaction continuously of camphor tree seed oil select ionic liquid 1-methyl-3-(3-sulfo-propyl) imidazole-toluene sulfonate as catalysis and conditions were:glycerol/camphor tree seed oil (mol/mol) 5.1:1, amount of catalyst 5.6%(oil weight), reaction temperature 153℃, reaction time 5.4h, on this reaction conditions, camphor tree seed oil monoglycerides yield can reach to 71.5%.Esterification and transesterification reaction step by step process conditions were:esterification reaction used ionic liquid 1-methyl-3-(3-sulfo-propyl) imidazole toluenesulfonate, reaction temperature 140℃, amount of catalyst 3.5%(oil weight), molar ratio glycerol to oil 2.2:1, reaction time 1.9h, esterification rate and monoglycerides yield were 96.3% and 16.7%. Transesterification reaction used NaOH as catalyst, reaction conditions were:reaction temperature 170℃, time 2.Oh, molar ratio glycerol to oil 6.5:1, amount of catalyst 0.5% (oil weight), on this reaction conditions monoglycerides yield can reach to 90.2%.Preparation of monoglycerides using esterification method suits raw material is the fatty acids. It is a simple technology, application widely, using 1-methyl-3-(3-sulfo-propyl) imidazolium hydrogen sulfate salt as catalysis, reaction time 2h, monoglycerides yield reach to 73.1%. Preparation of monoglycerides using esterification and transesterification continuously suits raw oil with high acid value and high moisture, using 1-methyl-3-(3-sulfo-propyl) imidazole toluenesulfonate as catalysis, reaction time 5.4h, monoglycerides yield reach to 71.5%. It has a simple process, easy to operate, but the low rate of acid catalyst and longer reaction time. Esterification and transesterification reaction step by step method use advantages of acid and alkali catalysts. It has a short reaction time and high-purity of monoglycerides yield. Esterification reaction used ionic liquid 1-methyl-3-(3-sulfo-propyl) imidazole toluenesulfonate and reaction time 1.9h, then transesterification reaction used NaOH as catalyst and reaction time 2h, monoglyceride yield can reach to 90.2% on this reaction conditions. It is a very good way to prepare high purity monoglycerides using esterification and transesterification reaction step by step method.1-decanoyl-rac-glycerol and glyceryl monolaurate prepared by cold saline washing, centrifugation and vacuum drying from camphor tree seed oil monoglycerides that through esterification and transesterification reaction step by step method.1-decanoyl-rac-glycerol and glyceryl monolaurate shows that 3376cm-1 was-OH stretching vibration peak by infrared spectrometry. The physical and chemical properties of 1-decanoyl-rac-glycerol and glyceryl monolaurate analyzed by GB15612-1995 and the results were:monoglycerides content 91.5%, iodine value 0.8 gI2/100g, solidification point 40-42℃, free fatty acid 1.2% arsenic 0.000033%, heavy metal (Pb) 0.000038%.Test 1-decanoyl-rac-glycerol and glycerol monolaurate emulsifying power of different oil-water ratio, the results show that 1-decanoyl-rac-glycerol and glycerol monolaurate have a stronger emulsifying power when oil-water ratio was 6:4 and it can reach to 65.1g/g. The amount of centrifugate stability was 4%, room temperature stability was 2.5% and high temperature stability was 3.5% of high-purity 1-decanoyl-rac-glycerol and glycerol monolaurate.At the same time we use national standard GB/T11543-2008 surface active agent-the identification of emulsion for moderate to hight viscosity and the evaluation method of emulsifying ability to study its emulsifying ability. Make stable emulsion that visual stability, storage stability, centrifugate stability and thermal cycles stability have best indexes when oil-water emulsion was 6:4, emulsion type (O/W),1-decanoyl-rac-glycerol and glyceryl monolaurate emulsifying ability was 28.0 g/g.
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