Glycosylation Synthesis And Properties Of Modified Waste Oil

Waste oil generally included all the productions of oil after repeated heating in human life.Due to its toxic and difficult to recycle,it has great potential danger to human health.To make waste oil harmless and utilize resource,thus,has become one of the important problems urged to be solved in the field of food safety.Since the main components of waste oil are animal and vegetable oil and fat,especially some fatty acid esters which carbon chain lengths is 16¹8.This experiment took waste oil as raw material,through the process of pretreatment,modification and glycosylation,finally found a method for preparing alkyl glycosides non-ionic surfactant by waste oil.In order to make waste oil meet the requirement of modification,pretreatment is very indeed.In this paper,activated carbon and activated bentonite are used as carriers.After alkali treatment,they can be used in the waste oil pretreatment of deacidification and decolorization,which can simplified waste oil pretreatment greatly.The optimal preparation conditions of solid base were AC/AB=6:4,NaOH solution concentration 10 g·L^-1 and the optimum parameters of treatment process were dosage of solid alkali 150 mg·g^-1,reaction time 30 min,reaction temperature 70?.After the pretreatment,the acid value of waste oil was 0.16 mg·g^-1,ultraviolet absorbance in 320 nm was 0.142,the phospholipid content<0.01%and the water content was 0.2%,which shown the method has a good effect.Transesterification of waste oil was observed to reduce the viscosity of the system and glycosylation reaction hindrance.The effects of different factors?temperature,reaction time,alcohol and oil mole ratio,catalyst dosage?have been determined and the optimum conditions were the catalytic additive dosage 0.8%,alcohol and oil ratio 6:1,reaction temperature 60?,reaction time 45 min.The yield was 96.6%and the content of fatty acid methyl ester was99.9%,which was analyzed by GC-MS.In the experiment of the reduction of fatty acid methyl ester,NaBH₄/metal salt were used.The effects of different factors?metal salt,NaBH₄dosage,solvent,etc.?on the reduction reaction of the ester have been determined and optimum conditions were waste oil methyl ester 10 mmol,NaBH₄ 20 mmol,AlCl₃ 40 mmol,THF 27 mL,MeOH 3 mL,reaction temperature 66?,reaction time 8 h.Under these conditions,fatty alcohol yield reached 90%.Then,reduced fatty alcohol and glucose were used for glycosylation reaction.Phase transfer catalyst was used to enhanced the activity and hexadecyl trimethyl ammonium bromide,tetrabutyl ammonium bromide,tetramethyl ammonium chloride and PEG-400,four phase transfer catalysts'performance were compared.The optimum conditions were reaction temperature 110/115?,reaction time 3 h,sugar and alcohol ratio 1:4,toluene sulfonic acid as the catalyst concentration was 1.5%?glucose mass ratio?,tetrabutyl ammonium bromide dosage 0.5%?glucose mass ratio?.The yield was 88%.With glycerol as carrier agent which aimed to optimize vacuum distillation to remove fatty alcohol,the results shows that when n?glycerol?/n?glucose?=0.7,residual alcohol content was 32%,which was much better than that without the addition of carrier agent.The APG product is white or yellowish paste or powder solid with no special smell.It has weak foaming performance and good emulsifying properties.Through the observation of super heavy oil emulsion with this APG product,it can be a kind of good emulsifier.