Process of making soap

REACTION OF SAPONIFICATION IN THE PROCESS OF MAKING SOAP The word saponification or saponify means making soap (Latin sapon, = soap and -fy is a suffix meaning to make). The ancient Romans began to make soap since 2300 years ago by heating the mixture of animal fat with wood ash. In the 16th and 17th centuries in Europe the soap was only used in the field of medicine. It was not until the 19th century widespread use of soap. Soap is made from the process of saponification of animal fats (tallow) and from oil. The fat broodstock is called fatty acids consisting of long hydrocarbon chains (C-12 to C18) that bind to form carboxyl groups. Short chain fatty acids are rarely used because they produce less foam. Saponification reaction is nothing but basic hydrolysis of an ester with alkali (NaOH, KOH), the general reaction is: O O // // R - C Na + OH - R - C + R`OH \ \ OR` O- Na + Alkaline salt ester of an alcoholic acid This mechanism involves the hydroxide ion nucleophile attack on carbonyl carbon : :: │ │ H: - + R - C - OR` R - C - OR` │ OH O O ║ ║ R - C - OH + -: R` R - C - O- + R`OH Strong base base bases For example saponification reaction of Glyceryl Tripalmitate with alkali NaOH: O ║ CH2OC (CH2) 14CH3 CH2OH │ CHOH │ CH2OH O ║ -OC (CH2) 14CH3 O ║ C Sodium palmitate H2OC (CH2) 14CH3 + 3Na + OH- + 3Na + Glycerol O ║ CH2OC (CH2) 14CH3 Glyceryl tripalmitate Another example is the saponification reaction of Glyceryl Tripalmitate with KOH alkali: O ║ CH2OC (CH2) 14CH3 CH2OH │ CHOH │ CH2OH O ║ -OC (CH2) 14CH3 O ║ C H2OC (CH2) 14CH3 + 3K + OH- + 3K + Glycerol O ║ CH2OC (CH2) 14CH3 Glyceryl tripalmitate Soap can be made by batch or continuous process In batch process, fat or oil is heated with excessive alkaline (NaOH or KOH) in a kettle. If the sapling has been finished, salt salt is added to soap. A layer of water in which salt, glycerol and excess alkali are removed and glycerol is recovered from the distillation process. Sludge soap deposits mixed with salt, alkali and glycerol are then purified with water and precipitated with salt over and over again. Finally, the sediment is boiled with enough water to obtain a subtle mixture that gradually forms a homogeneous and floating layer. This soap can be sold directly without further processing, ie as a cheap industrial soap. Some fillers are added, such as sand or pumice stone in the manufacture of scouring soap. Some treatments are needed to convert soap to powder soap, soap powder, medicine soap, scented soap, laundry soap, liquid soap and floating soap (by dissolving the air inside). In the continuous process, which is commonly done now, fat or oil hydrolysis with water at high temperature and pressure, assisted with a catalyst such as zinc soap. The fat or oil is inserted continuously from one end of the large reactor. The fatty acids and glycerol fIn general, the alkali used in soap making is generally only NaOH and KOH, but sometimes also using NH4OH. Soaps made with NaOH are slower to dissolve in water than with soaps made with KOH. The strong alkali soap (NaOH, KOH) has a pH value of 9.0 to 10.8 whereas a weak alkali soap (NH4OH) will have a lower pH value of 8.0 to 9.5. Soap is a salt of weak acids, the solution is slightly alkaline due to the presence of partial hydrolysis. O O ║ ║ R - C - O - Na + + H - OH R - C - OH + Na + OH - Alkali soap The alkali can mambahayakan some kind of textile, soap also can not work if the pH of the solution is too low. Because the long carbon chain will settle like foam. For example, soap from sodium stearate, will turn into stearic acid in an acidic atmosphere. O O // // C17H35C + H + Cl- C17H35C + Na + Cl- \ \ O- Na + OH Sodium stearate stearic acid In addition, soap usually forms salt with calcium, magnesium, or iron ions in hard water. The salts are not soluble in water. O // 2C17H35C + Ca ++ (C17H35COO) 2-Ca ++ + 2Na + \ O- Na + Sodium stearate calcium stearate (Soluble) (settles) The water-insoluble salt creates a brown color on the bathroom wall, a collar, or a dull color on clothes and hair. The problem is solved in several ways. For example by reducing calcium and magnesium ions and replacing them with sodium ions, or known as soft water. (Soft water). It can also add phosphate to the soap, because the phosphate forms a complex with metal ions, dissolved in water, preventing them from forming a salt of insoluble with soap. However, the use of phosphets should be limited, because if the flow in the lake or phosphate rivers that also serve as fertilizer will stimulate the growth of plants so large that the plants spend oxygen dissolved in the water and cause the fish to die. Alternatively, by substituting the carboxylic ionic group in a soap with a sulphate or sulphonate group. This is the way underlying the formation of detergents. In the subsequent development of soap form to be various, namely: Liquid soap Made from coconut oil Alkaline used KOH The form is liquid and does not thicken in room temperature Soap soft Made from coconut oil, palm oil or unbranched vegetable oil Alkaline used KOH Paste form and easily soluble in water Hard soap Made from solid neutral fats or from oils hardened by a hydrogenation process Alkaline used NaOH Hard to dissolve in water Women desperately want to use soap in liquid form, because the liquid form provides a lot of foam. Foam-containing soaps, especially in liquid soap made from coconut oil or copra, usually cause stimulation and allow the cause of dermatitis when used. That's why its use is replaced with olive oil and soybean oil or other oils that can produce softer and better soap. But the users do not like it because the soap is low solubility and does not provide a lot of foam. With the rapid development in the industrial world it is possible that the addition of other ingredients into the soap to produce soap with new properties and uses. Added ingredients for example: Soap health TCC (Trichorlo Carbanilide) Hypo allergenic blend, to cleanse fat and acne Salicylic acid as a fungicide Sulfur, to prevent and treat skin diseases Beauty soap Perfume, as perfume and aroma therapy Vitamin E to prevent premature aging Moisturizer Hydroquinone to whiten and brighten the skin Shampoo Diethanolamine (HOCH2CH2NHCH2CH2OH) to maintain the pH Lanolin as conditioner Protein to nourish the hair In addition to soap type above there are many other types of soap, such as toilet soap containing disinfectant and perfume. Textile soaps used in the textile industry as lifting the dirt on wool and cotton. Dry-cleaning soaps that do not require water for soluble and non-foaming, usually used as hand-washing soap packed in disposable packaging. Metallic soaps, which are salts of fatty acids reacted with alkaline earth and heavy metals, are commonly used for color dispersers in paints, varnishes, and lacquer. And salt-water soaps made from African palm oil (Elaise guineensis) that can be used for washing in saltwater. Although it is the main ingredient for forming soap, but it turns out alkali has a negative impact on the skin. Some investigators know that alkali is more damaging to the skin than its ability to remove oily ingredients from the skin. Nevertheless in its use with water, soap willormed are removed from opposite ends by means of distillation. These acids are then neutralized with alkali to be soap.