 |
As one of the important platform compounds, fatty alcohols are the basic chemical raw materials for the synthesis of surfactants, detergents, plasticizers and many other fine chemicals. They are widely used in textiles, daily chemicals, papermaking, and food. , medicine, leather and other fields. Our country is a big consumer of fatty alcohols. With the improvement of people's living standards, the demand for fatty alcohol series products and their derivatives is also gradually increasing.
Octadecanol, also known as 1-Octadecanol, is a small white waxy crystal with a fragrance. The relative density is 0.8124 (59/4℃), the melting point is 59℃, and the boiling point is 210.5℃ (15·133.322Pa). Insoluble in water, soluble in ethanol, ether and acetone. It can have a sulfonation reaction with concentrated sulfuric acid, but has no chemical effect when exposed to alkali. At present, stearyl alcohol is produced industrially by using stearic acid or methyl stearate as raw materials and using Cu-based catalysts for hydrogenation. Heptadecene fraction can also be obtained by controlling the polymerization of ethylene under the action of alkyl aluminum. , and then obtain octadecyl alcohol through oxo synthesis. Catalysts based on Cu-Cr are highly polluting and have high reaction requirements. Therefore, in recent years, scholars have continued to study Cu-based catalysts.
Investigate the catalytic performance of the catalyst for the hydrogenation of esters to produce alcohols; use the Cu-Zn-Zr catalyst to study the hydrogenation of fatty acid methyl esters to produce fatty alcohols, with a yield of 70%; investigate the Cu-Al-Ba catalyst, and the product yield is relatively High, but the reaction conditions are harsh and the amount of catalyst is large. The effect of the structure of the CuO/Zn O/Al 2O3 catalyst on the hydrogenation of oils to prepare fatty alcohols was studied, and the product yield was 98%. The effect of free fatty acids on Cu-based catalysts in the hydrogenation reaction of fatty acid methyl esters was studied. Free acids lead to a decrease in catalyst activity. The damage to the catalyst caused by free acids can be reduced by adding alkali.
As an important fatty alcohol, stearyl alcohol is widely used in chemical research, daily chemicals, textiles, printing and dyeing, medicine, cosmetics and other industries. It is used to manufacture plastic additives, surfactants, emulsifiers and various additives. of raw materials.
Octadecanol polyoxyethylene ether is a good dye leveling agent, with excellent emulsification and leveling properties, good warm viscosity and biodegradability. The product is nonionic in alkaline and neutral media, and cationic in acidic media. It can be used as a leveling agent for acidic complex dyes to reduce the amount of sulfuric acid in the dye bath and reduce strong damage to fabrics. It can also be used as a leveling agent for neutral dyes and vat dyes, and as a stripping agent for wool and nylon fabrics.
The preparation method uses stearyl alcohol and ethylene oxide as raw materials, and is prepared by polymerization in the presence of a catalyst; the weight ratio of the stearyl alcohol and ethylene oxide is 1:0.145~3.05; the catalyst It is any one or a mixture of more than one of solid sodium methoxide, sodium methoxide methanol solution, KOH, NaOH, etc., and its addition amount is 0.05~0.6% of the weight percentage of the prepared stearyl polyoxyethylene ether. The above method reasonably determines the raw material ratio, catalyst dosage, polymerization reaction temperature, time and other process parameters and conditions. The reaction conditions are mild, easy to control, and have low equipment requirements. The obtained stearyl polyoxyethylene ether has light color and stable performance. The range of adjustable molecular weight is large, and the dye leveling agent product with the required performance can be obtained by adjusting the molecular weight, which can meet the needs of various occasions.
Includes the following steps: first prepare the glycidyltrimethylammonium chloride intermediate, mix epichlorohydrin and trimethylamine, and react at 25-30°C for 4-5 hours to prepare glycidyl Trimethylammonium chloride intermediate; prepare maleic anhydride stearyl alcohol ester intermediate, mix maleic anhydride and stearyl alcohol, react at 70~75°C for 3~4 hours, and prepare maleic anhydride ten Octaol ester intermediate; heat the above-prepared stearyl maleic anhydride intermediate to 110-115°C, and slowly add the epoxypropyltrimethylammonium chloride intermediate to the stearyl maleic anhydride. In the intermediate, the adding time is controlled to 3 to 5 hours. After the addition is completed, the temperature begins to rise. When the temperature of the material reaches 120°C, the temperature is kept constant for 1 hour to obtain a maleic anhydride reactive emulsifier.
First add 0.3~0.8% polymerization inhibitor by weight of octadecanol into stearyl alcohol, heat it to completely dissolve it, then add 1.2~1.5 times the molar amount of octadecanol to acrylic acid and 0.5% by weight of octadecanol. ~1.2% catalyst, stir and mix; heat the mixture to 60~120℃, reflux for 2~3 hours, separate the water generated by the reaction, continue to heat to 130~140℃, keep the reaction for 2~4 hours, and distill under reduced pressure Remove the unreacted acrylic acid and residual water, and then wash the reaction product with caustic alkali aqueous solution, then with water until neutral; finally, vacuum dry at 40°C for 6 to 8 hours to obtain waxy solid stearyl acrylate.
The present invention has the advantages of fast reaction rate, high reaction selectivity, short reaction time, high ester yield, and easy release of product water. It does not use entrainers and avoids serious pollution caused by toxic solvents. The problem belongs to the clean production process.
Method 1: The Cu-Al-Ba catalyst prepared by co-precipitation method has high activity and selectivity for the liquid-phase catalytic hydrogenation of methyl stearate to prepare stearyl alcohol. Catalysts prepared by countercurrent co-precipitation, treated with organic solvents and then dried have smaller CuO crystal grains, which is beneficial to improving catalytic activity.
The optimal synthesis process conditions are: using the countercurrent co-precipitation method, preparing the catalyst by drying after treatment with organic solvents, the reduction temperature is 250~400°C, w (catalyst) = 3%, the reaction pressure is 6MPa, and the reaction temperature is 240 ℃, reaction time 5h, under these process conditions, the conversion rate of methyl stearate is 998%, and the selectivity of stearyl alcohol is 96.6%. Treat methyl stearate with 0.02mol/L sodium hydroxide, let it stand for separation, remove the water layer, and then dry the obtained methyl stearate at 80°C. The purpose is to lower the acid value and reduce the impact of residual stearic acid on the stability of the catalyst. The reaction formula is as follows:
Methyl stearate is hydrogenated and reduced under the action of a catalyst to produce stearyl alcohol and methanol. The reaction formula is as follows:
Side reaction: Hydrodecarboxylation of methyl stearate to generate heptadecane:
When octadecyl alcohol is generated, octadecanol is further hydrogenated under the action of Cu catalyst to form octadecane.
Method 2: A method for preparing stearyl alcohol through hydrodeoxygenation conversion of stearic acid. Stearic acid, n-heptane and Ni/m-ZrO2 catalyst are added to a high-pressure reactor, in which stearic acid and n-heptane are added. The mass/volume ratio is 0.4/100 (g/ml), fill with H2, and stir the reaction at 240°C and a rotating speed of 1000r/min. The mass of stearic acid is 0.4g, and the volume of n-heptane is 100 mL. The active component of the catalyst is Ni, the carrier is highly defective monoclinic phase nano-ZrO2, and the specific surface area is 50-150m2/g. The loading of catalyst Ni is 3%, the catalyst mass is 8-10% of the stearic acid mass, preferably 0.036g, and the H2 pressure is 5.5MPa.
[1] Dictionary of Organic Compounds
[2] Preparation of stearyl alcohol by hydrogenation of methyl stearate
[3] Synthesis method of CN200710164802.6 stearyl polyoxyethylene ether
[4] CN201810593208.7 Preparation method of maleic anhydride reactive emulsifier
[5] CN200810018016.X Process for preparing stearyl acrylate by melt esterification method
[6] CN201810305121.5 A method for preparing stearyl alcohol through hydrodeoxygenation conversion of stearic acid
 |
Contact
Contact