Tall oil soaps

Tall oil rosin Tall oil rosin pOR) Tall oils Tall oils acids Tall-oil soaps Tallow... 

In the initial black Hquor concentration, saponified fatty and resin acid salts separate as tall oil soaps (see Tall oil). These soaps can be skimmed from the aqueous spent Hquor, acidified, and refined to give a cmde tall oil composed of resin acids, chiefly abietic and neoabietic fatty acids, chiefly oleic and Hnoleic and an unsaponifiable fraction made of phytosterols, alcohols, and hydrocarbons. Tall oil is fractionated primarily into fatty acids (see... 

Process Sequence. The process sequence consists of recovery of tall oil soap from the pulping blackhquor, acidulation, ie, conversion of the soap into CTO with sulfuric acid, fractional distillation to separate rosin, and fatty acids and purification of the fatty acid fraction. 

Black Liquor Soap Recovery. Black Hquor soap consists of the sodium salts of the resin and fatty acids with small amounts of unsaponifiables. The soap is most easily separated from the black Hquor by skimming at an intermediate stage, when the black Hquor is evaporated to 25% soHds (7). At this soHds level, the soap rises in the skimmer at a rate of 0.76 m/h. At higher soHds concentrations, the tall oil soap is less soluble, but higher viscosity lowers the soap rise rate and increases the necessary residence times in the soap skimmer beyond 3—4 hours. The time required for soap recovery can be reduced by installing baffles, by the use of chemical flocculants (8,9), and by air injection into the suction side of the soap skimmer feed pump. Soap density is controUed by the rate of air injection. Optimum results (70% skimmer efficiency) are obtained at a soap density of 0.84 kg/L (7 lb/gal). This soap has a minimum residual black Hquor content of 15% (10—12). 

Two other important side products of the kraft process are sulfate turpentine and tall oil. The turpentine is obtained from the gases formed in the digestion process. From 2-10 gal of turpentine can be obtained per ton of pulp. Tall oil soap is a black viscous liquid of rosin and fatty acids that can be separated from the black liquor by centrifuging. Acidification gives tall oil. These side products will be discussed later. 

The neutral or unsaponifiable materials present in tall oil include anhydrides, pheno-lics, diterpene aldehydes and alcohols, stil-benes, and steroids. In the neutral fraction of southern pine tall oil soap, 80 compounds have been identified. They include 25.1 percent sistosterol and a total of 32.4 percent steroids. The sistosterol content of crude tall oil is 2-3 percent and is the main component of the neutral fraction. 

Crude tall oil is a mixture of fatty acids, resin acids, and neutrals (i.e., no carboxylic acid functionality). The background section relates that neutrals interfere with the separation of the fatty acids from the resin acids and in industrial practice the neutrals are removed by molecul distillation. However, it is difficult to separate the neutrals from the other components because of vapor pressure similarity considerations. Tall oil soap, the precursor to crude tall oil, is a pasty emulsion of the neutrals and the sodium salts of the fatty and resin acids. The patent states that it is possible to extract neutrals from the soap with a liquid hydrocarbon solvent, but the prior art discussion relates that subsequent liquid hydrocarbon solvent recovery steps are relatively difficult. The neutrals can be separated from the soaps by a hydrocarbon solvent, incidentally, because the neutrals are lipophiles whereas the soaps are ionic and do not dissolve in the hydrocarbon. Similarly the neutrals will dissolve in a supercritical fluid like ethylene, or propane, or the chlorofluorocarbons, and the use of these gases in the supercritical state is the invention. Like the case of liquid hydrocarbon solvents, the ionic soap compounds will not dissolve in the supercritical gases. CO2 is specifically not listed among the gases, and we shall discuss the case of CO2 extraction of the emulsion later which is the subject of the next patent. 

The figure shown on the patent face page is a flow chart of the laboratory apparatus which was used to carry out the test. A sample of 15 g tall oil soap was charged to the extractor 22 the charge contained 4.9% neutral oil. The sample was exuacted with ethylene at 4000 psi, 70 °C. An extract sample weighing 0.54 g was analyzed and was found to contain 64% neutrals which represented almost one-half the neutrals present in the charge. The identity of the other 36% fraction of the extract was not reported but probably consisted of free resin and fatty acids. 

Returning now to the patent, the invendon taught is the contacting of crude tall oil soaps (a moist mixture of neutrals and sodium salts of fatty and resin acids) with CO2. The CO2 converts the salts to free fatty and resin acids which then dissolve in the CO2 (but probably so are some of the neutrals). One example describes a laboratory test that reports that from a charge of 9.65 g tall oil soap five fractions were extracted with supercritical CO2. The first fraction contained 88% resin + fatty acids, and the fifth fraction contained 72% resin. 

EINECS 263-136-1 Fatty acids, tail-oil, potassium salts Potassium soap of tall oil fatty acids (C18) Potassium tallate Tall oil acids, potassium salt Tall oil fatty acids, potassium salt Tall oil, potassium salt Tall oil soaps, potassium. 

Practically the only commercial successful innovations made by Finnish chemists in the early 20th century were related to tall oil soap and some other byproducts of woodpulping. The Finnish scholar Alfons Hellstrom discovered two more natural terpenes from juniper resin, invented methods for distilling tall oil under vacuum from sulphate pulping waste, and developed commercially applicable processes for the manufacture of tall oil soap and the use of rosin acids from tall oil for paper sizing. Such distillations of tall oil became an important industry not only in Finland but also in many other countries. By 1939, the sales of tall oil soap conquered a third of the Finnish detergent market. ... 

Tall oil soap n. Product formed by the saponification or neutralization of tall oil with organic or inorganic cases. 

The availability of the crude turpentine and tall oil soap by-products in a mill is strongly dependent on the wood species used for pulping, the method and time of storing logs and chips and the growth conditions of the trees. However, even among extractive-rich pine species, there is significant variation in the availability of these by-products. 

The tall oil soap is removed from black liquor due to density differences during the black liquor evaporation process (the optimum dry solids content is 28—32%), and the... 

ArpiainenV. Production of light fuel oil from tall oil soap liquids by fast pyrolysis feckra Hts. Licentiate s Thesis. Jyvaskyla, Finland University of Jyvaskyla, Laboratory of Apphed Chemistry 2001. 51 p [In Finnish]. 

Foran CD. Tall oil soap recovery. 2006. http //www.tappi.org/content/events/08kros/manuscripts/3-7.pdf. [accessed 29.05.14]. 

Despite the electronic communications revolution, paper production continues to grow worldwide at a rate of 2% to 3% annually. Much of the incremental increase is based on pine because no other long-fibered softwood offers such high yield rates per hectare coupled with a short growth cycle. New kraft pine pulpmills and most existing mills will continue to practice tall oil recovery because non-removal of tall oil soap from kraft black liquor adversely affects evaporator and recovery boiler capacity (14). Increased tall oil production has been accompanied by new fractionator capacity in Europe and incremental expansion in the United States. Since the paper industry is the largest user of rosin size, it might be expected that the increased paper production would absorb the increased availability of tall oil rosin. 

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