What are the equipment and operations of the saponification reaction experiment of oils and fats?
Production of soap
1. Principle
Oil and sodium hydroxide are boiled and hydrolyzed into higher-order fatty acid sodium and glycerin, and the former is processed into shape Then there's soap.
2. Supplies
One 150 and 300mL beaker, glass rod, alcohol lamp, asbestos net, tripod, lard (or other animal and vegetable fats or oils), NaOH, 95 % alcohol, saturated saline.
3. Operation
(1) In a 150mL beaker, put 6g of lard and 5mL of 95% alcohol, and then add 10mL of 40% NaOH solution. Stir with a glass rod to dissolve (heat over low heat if necessary).
(2) Place the beaker on an asbestos mesh (or in a water bath), heat over low heat, and stir constantly with a glass holder. During the heating process, if the alcohol and water are reduced by evaporation, they should be replenished at any time to maintain the original volume. For this purpose, 20mL of a mixture of alcohol and water (1:1) can be prepared in advance for new additions.
(3) After heating for about 20 minutes, the saponification reaction is basically complete. If testing is required, a few drops of sample can be taken out from a glass rod and put into a test tube. Add 5 to 6 mL of distilled water to the test tube and heat and shake. When left to stand, if grease separates, it indicates that the saponification is incomplete. Alkali solution can be added dropwise to continue saponification.
(4) Slowly add 20mL hot distilled water to the completely saponified viscous liquid, and stir to make them dissolve. Then slowly pour the viscous liquid into 150 mL of hot saturated salt solution and stir while adding. After standing, the soap will salt out and float. After all the soap has separated and solidified, it can be taken out with a glass rod, and the soap is ready.
4. Description
(1) Oil is not easily soluble in alkaline water. Alcohol is added to increase the solubility of oil in alkali solution and speed up the saponification reaction.
(2) If a water bath is not used for heating, a low fire must be used.
(3) During the saponification reaction, the original volume of the mixture must be maintained, and the mixture in the beaker must not be boiled dry or spilled out of the beaker. Note: Saponification reaction: hydrolysis reaction of oil under alkaline conditions.
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Soap making technology
1. Production tools: 1 iron pot (or steel plate), a wooden table for cutting 1, 1 wooden bench for typing, 2-4 printing dies (wooden), several iron boxes for holding soap, and several wooden racks for drying soap. The above tools can be made by hand.
2. Required raw materials: oil sludge (leftovers from vegetable oil pressing plants, also called oil feet and oil residue), animal oil (cow, horse, sheep, and lard are all acceptable), caustic soda, rosin , water glass (sodium soda), salt, soap essence, soap yellow.
3. Soap base production
1. Saponification. Add 15 kilograms of water to the soap pot and 4-5 kilograms of caustic soda. Burn over fire until all caustic soda melts, add 50 kg of oil sludge, continue heating and stirring continuously. After 30 minutes, all the sludge melted away. At this time, use medium or low heat to continue heating and stir continuously to fully saponify the sludge. The resulting higher-order fatty acid sodium is the main component of soap. Because the quality of sludge is different, the length of saponification time is also different. After all the oil sludge has melted, add the amount of caustic soda according to the conditions in the pot. If stratification occurs, it means that the soap has been "separated" (the soap is separated from the water). If the soap still sticks to the shovel after lifting it from the pot, it means that the water has not been "watered out" yet. You need to add a small amount of caustic soda water. Wait for 5 minutes. If the soap still does not "water out", you can add another time. , until "water separation" occurs.
2. Salting out. After "water separation", in order to separate the impurities and sewage in the soap liquid in the pot, add 1.5 kilograms of salt and stir to fully dissolve the salt. At this time, using a shovel to test "water separation" will be more obvious. After salting out, continue heating for 5-10 minutes, then stop heating and stirring. Cover the pot with insulation material and let it sit for 3-5 hours before serving. When it comes out of the pot, take out the upper layer of soap liquid and put it in the iron soap box to become the soap base. The glycerin can be extracted from the lower layer of sewage. If the color of the soap base that comes out is poor, you can boil it 1-2 more times according to the above method.
4. Production of finished products: First add 20 kilograms of water and 4 kilograms of caustic soda into the pot.
After the caustic soda melts, add 40 kilograms of soap base, 8 kilograms of animal oil, and 2 kilograms of rosin. Continue heating and stirring. After all the materials in the pot have melted and saponified, check whether the water has been separated. If the water has not been "divided" yet, you can add some more caustic soda water until the water is "divided". After the soap liquid is separated from the water, stop heating and stirring, cover the pot with insulation material, and let it sit for 10 hours before taking it out of the pot. When taking out the pot, first take out the soap foam on the upper layer (it can be returned to the pot for reuse during next processing), then take out the soap liquid and place it in an iron soap box (if agglomeration occurs, it is because the temperature in the pot was too high when it was kept warm and left to stand). If it is too low, it can be reheated to dissolve, let it stand and then take it out of the pot). At the same time, add 4 kg of caustic soda, 0.5 kg of soap essence, and a trace amount of soap yellow. Stir while adding until mixed, then cool to solidify.
5. Cutting, printing and packing:
1. Pour out the cooled soap from the iron box and cut it into three large pieces with thin steel wire (or iron wire); The steel wire dicing wooden table cuts large pieces of soap into soap bars, and the cut scraps can be reused in the pot next time.
2. Place the cut soap bars on the soap drying rack to dry until they are no longer sticky to your hands. Then you can start printing. That is, place the soap bars in the typing mold to print. After printing, place on the soap rack to dry. After boxing and packaging, it is the finished product. Experiments on the saponification reaction of oils and fats
The water has been saturated with salt, and the concentration of sodium ions in it has reached the maximum. If sodium higher-order fatty acid is added, it will be insoluble in water, that is, "precipitated". What does the saponification reaction of oil and fat refer to?
The -co-o- bonds of oil and fat break, and react with the metal ions and -OH hydroxyl groups of the alkali metal solution to form metal salts (soap) and alcohol respectively. What type of saponification reaction does oil have?
The saponification reaction types of oils and fats are: substitution reaction and hydrolysis reaction.
Saponification reaction usually refers to the reaction of alkali (usually strong alkali) and ester to produce alcohol and carboxylate, especially the reaction of oil and alkali.
In a narrow sense, the saponification reaction is limited to the reaction of mixing oils and fats with sodium hydroxide or potassium hydroxide to obtain sodium/potassium salts of higher-order fatty acids and glycerol. This reaction is a step in the process of making soap, hence its name. Its chemical reaction mechanism was discovered by French scientist Eugène Chevreul in 1823.
In addition to the common reaction between grease and sodium hydroxide, the saponification reaction also involves the reaction between grease and concentrated ammonia. The hydrolysis reaction of oil and fat is a saponification reaction
No
When hydrolyzed in an alkaline environment, it is a saponification reaction, but when hydrolyzed in an acidic environment, it is not
Saponification reaction equation
CH2OCOC17H35
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CHOCOC17H35 + 3NaOH → 3C17H36-COONa + CH2OH-CHOH-CH2OH
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CH2OCOC17H35 Saponification reaction of stearic acid glycerol
C17H35COOH+NaOH->C17H35COONa+H2O The hydrolysis of oils and fats is a saponification reaction, which is wrong?
Oils and fats can be used in acidic and alkali conditions Hydrolysis under the action of sex or pancreatic lipase. Only hydrolysis under alkaline conditions to produce soap is called saponification reaction. The hydrolysis reaction of oil under the action of acid or pancreatic lipase is not a saponification reaction. Regarding the saponification reaction of fats and oils in chemistry
Because sodium higher-order fatty acids are the main component of soap, and alkaline hydrolysis is sodium higher-order fatty acids, not higher-order fatty acids. When I make my own handmade soap, the hydrolysis reaction of fats and oils is Is it a saponification reaction?
There are hydrolysis conditions: alkaline conditions
Saponification reaction usually refers to the reaction of a base (usually a strong base) and an ester to produce alcohol and carboxylate , especially the reaction between oil and alkali.
In a narrow sense, the saponification reaction is limited to the reaction of mixing oils and fats with sodium hydroxide or potassium hydroxide to obtain sodium/potassium salts of higher-order fatty acids and glycerol. This reaction is a step in the process of making soap, hence its name.