Supplemental information about glycerine Some information on glycerine production development

      Glycerine has been discovered in 1779 by a Sweedish researcher Karl Sheele, who has discovered, that while heating olive oil with lead oxide one obtains a substance with a sweet taste. Further evaporation of substance has allowed him to get a syrop-like heavy liquid.
      Subsequently, K.Sheele has proved, that all fats and oils have a sweet basis in their structure. For a long period technical glycerine has been obtained with the use of Sheele method: fatty materials were treated with lead oxyhydroxide solution, the obtained lead fatty acids salts were settled with hydrogen sulfide and the glycerine solution was evaporated till the getting of the finished product.
      In the beginning of the XIX th century the number of glycerine applications has grown up and this lead to the necessity to increase the amounts of its production. For the first time the sweet liquid was called glycerine in 1811 by a French chemist Michel Eugene Chevrel. After that were defined fatty acids ethereous chemical formulas as well as glycerine formulas in vegetable oils and animal fats. He has been given a patent to produce fatty acids from fatty materials treating them with lime and other alkalis proceeding to soap decomposition by sulphuric acid. In such a way was discovered the first industrial method of getting technical glycerine by means of neutral fats oxyhydroxide saponification with further glycerine extraction from soap leaches. Nowadays this method is used in all countries of the world.
      The second industrial method to obtain glycerine was discovered in 1853 by A. Tilgman. Using intensive mixing and pressure, the fats, heated with water are splitted into fatty acids and glycerine at the temperature of 175-200 °С the process takes from 10 to 12 hours. Being cooled the fatty acids float on surface of the glycerol water. At present this method to get glycerine is mainly used in our country.
      The further important step in glycerine production development was publishing of the description of glycerine distillation with water vapor by Wilson in 1856. Demand for such purified glycerine has grown after in 1847 Askanio Sobrero has obtained glycerin nutric acid, called glycerol trinitrate, having explosive properties.
      In 1853 one of the Russian scientists N. Zinin has lead experiences on nitroglycerin technical applications in conditions of the Crym war. Having considered his works Alfred Nobel, a sweedish engineer and entrepreneur has obtained the explosive material in 1862.
      First a plant producing explosive materials on basis of the nitroglycerine was set up in Stockholm under A. Nobel's management, but it has been destroyed in 1864 as a result of an explosion. In 1867 A. Nobel has discovered that kieselguhr absorbs the threefold quantity nitroglycerin obtaining a flexible practically non-dangerous product, the dynamite. In 1875 A. Nobel has discovered the fulminic jell, which is a mixture of nitroglycerine and nitrocellulose and in 1888 he has obtained the nitroglycerine powder.
      In Germany a plant producing explosive materials was settled in 1865 in the city of Krummel. In the course of the 1st World War there were produced up to 25 tones nitroglycerine a day.
      Facts concerning world crude (80%) glycerine production are of great interest: in 1890 production was estimated at 40,000 tones, from which 40 tons were obtained as a result of stearine production and 14 tons - from soap alkolis. Data on world crude (80%) glycerine production are of great interest. In 1890 the world output has reached 40,000 tones, while 26,000 tonnes were obtained as a result of stearine production, and 14,000 - from soap alkalis. In 1910 world glycerine output was estimated at 80,000 tones, the major quantity being obtained from soap alkalis. The output of stearic acid had decreased as the begin to use paraffin candles and electric lightening.
      This period foreign countries mainly used oils and fats splitting in autoclave machines with fatty acids and glycerine obtaining. Fatty acids were refined and used in alimentary industry.
      In 1913 world crude glycerine output was estimated at 90, 000 tones, in the USA - at 20,000 tones, from which 1,000 tones - from soap alkalis and 3,000 tones - at stearic acid production; in England - 13, 000 tones, from which 5,500 tones - from soap alkalis; in France - 14,000 tones, from which 3,500 - from soap alkalis and 6,000 - at stearic acid production; in Germany - 9,000, from which 2,000 - from soap alkalis and 3,000 tons - at stearic acid production. The rest of the glycerine was outworked with autoclave method. In Russia, Austria and Holland as a result of stearic acid production were obtained 2,000 tons crude glycerine. Other countries also produced glycerine, but the output wasn't large.
      After the method of glycerine distillation with water steam has been discovered, for some 30 years they used heated steam (260-290 °С) to get higher quality material by means of heating crude glycerine to 200-220 °С. Since 1882 the process of distillation had been held at lower temperature in vacuum conditions. The first distillation facilities were introduced by such companies as "Hekman" and Scott. Glycerine heating was carried out by means of fire furnace. Admixtures content was considerable and the yield of the distilled product wasn't large.
      In 1898 has been created Twitchel's method, which included fats splitting in presence of emulsifying agents - sulphoacids. One of the catalysts for fats splitting was obtained by means of benzol, naphthalene, fatty acids and sulfuric acid interaction. Sulphoacids, obtained in result of this reaction are substantial and are not subject to decomposition being boiled with water and splitted fatty acids.
      Twitchl's catalyst reduces surface tension of the water-fat system and is a source of hydrogen cations, necessary to accelerate the hydrolysis reaction. The disadvantage of this method is the long-lasting splitting process (40 hours) and products darkening.
      In 1912 G. Petrov has proposed to use sulophopetroleum acids as contact splitting catalyst. Petrov's method is used at petroleum distillates processing with concentrated sulfuric acid. In such a way sulphoacids and liquid asphalt are obtained and then removed. Gas-oil contact is the most spread kind of contact.
      Petrov's method has allowed to decrease the period of time taken by the splitting process to 23-26 hours, to increase the depth of the splitting to 92%, to reduce steam consumption and admixtures content and to get purer fatty acids. The new method has been widely spread in the USA, in Europe and Russia.
      One must notify that for the last 150 years glycerine has been obtained from fats and oils by means of fatty substances saponification and getting glycerine from soap leaches or by means of splitting at presence of water condensate using autoclave facilities, then are obtained fatty acids and glycerol water.
      Further development of the glycerine industry is directed to facilities updating, technologies and glycerine quality improvement, production processes automation but the mentioned above technological schemes stay invariable.
      >Reference information.
Distillated Glycerine Chemical and physical analysis results.