Tuesday, 29 May 2012

glycerine soap

Make a soap with glyceriene, very easy to make.

Friday, 14 May 2010

Saponification another description

We are adding different types of description for saponification term, so you can understand it easly and can see the difference easly. Perspective is important factor in education. It is the reaction between a strong base (such as sodium or potassium hydroxide) and a natural fat. The products are glycerol and the alkali metal salts (soaps) of all the fatty acids that comprised the fat.

The reaction need not be "slow" if the concentration of the base is relatively high. Hydrolysis of fats (a reaction between the fat and hot water) to produce glycerol and free fatty acids released from the fat can be a relatively slow reaction because the fat and water are not mutually soluble one in the other. Typically, hydrolysis of fats is accomplished by use of high pressure steam rather than plain hot water.

Why is saponification a slow reaction?

One of student is asking a question about saponification process reaction speed to a specialist. Answer here: The saponification reaction is the reaction of an ester: R'--CO2--R with water to produce an alcohol, ROH and a carboxylic acid R'--CO2--H.

If R is a so-called "good" leaving group, the reaction can be quite smooth requiring only minutes to an hour or so. For "poor" leaving groups, for example, 2-methyl hexyl alcohol, the reaction can be quite sluggish, on the minute/hour time scale. There is also a lot of slack in those times because the presence of a catalyst for example, (H+) or (OH-), among many others cans reduce the reaction time. The temperature at which the reaction is run is also important. In the case of saponification reactions higher temperatures speed up the rate of reaction. The solvent also plays a contributing role. For example if the ester is water soluble and water is the reaction solvent, the rate of the saponification reaction is greatly increased. On the other hand, if the leaving alcohol group is R--OH, and the alcohol R--OH is used as the solvent the rate of saponification will be substantially suppressed.

Vince Calder

Wednesday, 14 April 2010

Antibacterial soap and regular soap

Antibacterial Soap No Better Than Regular Soap, NIH-Funded Study Shows. CHICAGO - October 24, 2002 - Despite medical experts' doubts that antibacterial soap is a better germ-killer than regular soap, half to two-thirds of hand cleansers on store shelves are labeled as antibacterial. Now a National Institutes of Health (NIH)-funded study confirms what medical experts have suspected. Results are being presented here at the 40th Annual Meeting of the Infectious Diseases Society of America (IDSA).

Saponification definitions from different sites

  • a chemical reaction in which an ester is heated with an alkali (especially the alkaline hydrolysis of a fat or oil to make soap)

  • Saponification is the hydrolysis of an ester under basic conditions to form an alcohol and the salt of a carboxylic acid (carboxylates). Saponification is commonly used to refer to the reaction of a metallic alkali (base) with a fat or oil to form soap.

  • The reaction of an ester with a metallic base and water, ie the making of soap.

  • The deposit of a gray scum or gray dust on the inside surface of a subgrade wall or floor; as the result of moisture moving through the concrete and washing certain chemicals from the concrete mass.

  • The breaking down of oils into very fine droplets called colloids; to hydrolyze a fat with alkali to form a soap and glycerol.

  • A chemical reaction involving the breakdown of triglycerides to component fatty acids, and the conversion of these acids to soap.

  • Alkaline hydrolysis of fats to make soaps.

  • The chemical reaction that occurs when a strong akali is combined with whole oils. Soap and glycerin are the end products.

  • A coating defect caused by the reaction of the binder with the substrate or attack of the film by an alkali resulting in a "soapy" film.

  • A chemical decomposition of a paint's binder by alkali and moisture from a substrate (eg, new concrete or fresh plaster)

  • The chemical reaction which converts a fatty acid (vegetable oils) and an alkali (sodium hydroxide) into soap and glycerin when you combine them in the proper ratio within a specific temperature range.

Sunday, 7 March 2010

Saponification experiment

Saponification experiment .. lab experiment..