Tall rosin

Rosin is classified into three main types viz. (a) gum rosin, (b) wood rosin, and (c) tall rosin l. Gum rosin is obtained as the residue in the spirit of terpentine from crude terpentine pitch by distillation. Wood rosin is produced by naphtha extraction... 

Rosin is a complex mixture of naturally occurring high molecular weight organic acids and related materials. Rosin obtained from various fractions of exudates of pine trees, known as gum rosin, wood rosin and tall rosin, is composed of about 90% resin acids and 10% neutral materials (Table 1). The resin acids are isomeric monocarboxylic acids of alkylated hydrophenanthrene nu-clei l 2. 

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

Table 8. UOP Sorbex Separation of Fatty Acids from Rosin Acids in Distilled Tall Oil...

Polyols. Several important polyhydric alcohols or polyols are made from formaldehyde. The principal ones include pentaerythritol, made from acetaldehyde and formaldehyde trimethylolpropane, made from -butyraldehyde and formaldehyde and neopentyl glycol, made from isobutyraldehyde and formaldehyde. These polyols find use in the alkyd resin (qv) and synthetic lubricants markets. Pentaerythritol [115-77-5] is also used to produce rosin/tall oil esters and explosives (pentaerythritol tetranitrate). Trimethylolpropane [77-99-6] is also used in urethane coatings, polyurethane foams, and multiftmctional monomers. Neopentyl glycol [126-30-7] finds use in plastics produced from unsaturated polyester resins and in coatings based on saturated polyesters. 

Alginates, alkaloids, glycerides, gutta, phenols, rosins, rubber, saponins sterols, tall oils, tannins, terpenes, waxes... 

The fine mica fraction is deslimed over 0.875—0.147-mm (80—100-mesh) Trommel screens or hydrocylcones, or is separated with hydrosi2ers. The deslimed pulp (<0.589 mm (—28 mesh)) of mica, feldspar, and quart2 is then fed to a froth flotation circuit where these materials are separated from each other either by floating in an acid circuit with rosin amine and sulfuric acid (2.5—4.0 pH), or an alkaline circuit (7.5—9.0 pH) with tall oil amine, goulac, rosin amine acetate, and caustic soda (see Eig. 2). 

Production. Rosin is isolated from pine trees, principally from longleaf Pinuspalustris slash Pinus ellioti and lobloUy pine Pinus taeda. The products are known as gum, wood, or tall oil rosin, based on the method of isolation and the source. 

Tall oil rosin is a by-product of paper manufacturing. Raw wood chips are digested under heat and pressure with a mixture of sodium hydroxide and sodium sulfide. Soluble sodium salts of lignin, rosin, and fatty acids are formed, which are removed from the wood pulp as a dark solution. The soaps of the rosin and fatty acids float to the top of the mixture, where they are skimmed off and treated with sulfuric acid to free the rosin and fatty acids. This mixture, known as cmde tall oil (CTO), is refined further to remove color and odor bodies fractional distillation separates the tall oil rosin acids from the fatty acids (see Tall oil). 

Typical grades of tall oil rosin also contain about 2—5% of acids. 

Eatty acid soap was first used for ESBR. Its scarcity prompted the investigation of rosin acids from gum and wood as substitutes (1). The discovery of the disproportionation of rosin allowed rosin acid soaps to overcome the polymerization inhibition of untreated rosin acids. Rosin acid soaps gave the added benefit of tack to the finished polymer. In the 1990s, both fatty acid and rosin acid soaps, mainly derived from tall oil, are used in ESBR. 

Table 17. Polyoxyethylene Esters of Rosin, Tall Oil, and Fatty Acids ...

The principal constituents of rosin (qv) are abietic and related acids. Tall oil (qv) is a mixture of unsaturated fatty and aHcycHc acids of the abietic family. Refined tall oil may be high in rosin acids or unsaturated acids, depending on the refining process. Ethoxylates of rosin acids, eg, dehydro abietic acid, are similar to fatty acid ethoxylates in surfactant properties and manufacture, except for thek stabiHty to hydrolysis. No noticeable decomposition is observed when a rosin ester of this type is boiled for 15 min in 10% sulfuric acid or 25% sodium hydroxide (90). Steric hindrance of the carboxylate group associated with the aHcycHc moiety has been suggested as the cause of this unexpectedly great hydrolytic stabiHty. 

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 Acidulation. Only two-thirds of a typical black Hquor soap consists of the sodium salts of fatty acids and resin acids (rosin). These acids are layered in a Hquid crystal fashion. In between these layers is black Hquor at the concentration of the soap skimmer, with various impurities, such as sodium carbonate, sodium sulfide, sodium sulfate, sodium hydroxide, sodium Hgnate, and calcium salts. This makes up the remaining one-third of the soap. Cmde tall oil is generated by acidifying the black Hquor soap with 30% sulfuric acid to a pH of 3. This is usually done in a vessel at 95°C with 20—30 minutes of vigorous agitation. Caution should be taken to scmb the hydrogen sulfide from the exhaust gas. 

Distillation. Separation of rosin from fatty acids is an essential step in utilizing CTO. The basic patent for tall oil distillation was granted in 1911 and the first commercial plant was constmcted in Kotka in 1913 (21), making Finland the birth place of the tall oil industry. In the United States,... 

The cmde tall oil fatty acids obtained from the rosin column usually contain about 5% rosin because the boiling points of the heavier fatty acids and the lighter resin acids overlap. By adding the intermediate fraction to the fatty acid, rosin does not have to be redistilled. 

Wood is the raw material of the naval stores iadustry (77). Naval stores, so named because of their importance to the wooden ships of past centuries, consist of rosin (diterpene resin acids), turpentine (monoterpene hydrocarbons), and associated chemicals derived from pine (see Terpenoids). These were obtained by wounding the tree to yield pine gum, but the high labor costs have substantially reduced this production in the United States. Another source of rosin and turpentine is through extraction of old pine stumps, but this is a nonrenewable resource and this iadustry is in decline. The most important source of naval stores is spent sulfate pulpiag Hquors from kraft pulpiag of pine. In 1995, U.S. production of rosin from all sources was estimated at under 300,000 metric tons and of turpentine at 70,000 metric tons. Distillation of tall oil provides, in addition to rosin, nearly 128,000 metric tons of tall oil fatty acids annually (78). 

Tall oil fatty acids (TOFA) consist primarily of oleic andlinoleic acids and are obtained by the distillation of crude tall oil. Crude tall oil, a by-product of the kraft pulping process, is a mixture of fatty acids, rosin acids, and unsaponiftables (1). These components are separated from one another by a series of distillations (2). Several grades of TOFA are available depending on rosin, unsap oniftable content, color, and color stabiUty. Typical compositions of tall oil fatty acid products are shown in Table 1 (see Tall oil). 

CAS Registry Cmde tall Cmde fatty <2% Rosin in fatty Distilled tall oil. 

Many similar hydrocarbon duids such as kerosene and other paraffinic and naphthenic mineral oils and vegetable oils such as linseed oil [8001-26-17, com oil, soybean oil [8001-22-7] peanut oil, tall oil [8000-26-4] and castor oil are used as defoamers. Liquid fatty alcohols, acids and esters from other sources and poly(alkylene oxide) derivatives of oils such as ethoxylated rosin oil [68140-17-0] are also used. Organic phosphates (6), such as tributyl phosphate, are valuable defoamers and have particular utiHty in latex paint appHcations. Another important class of hydrocarbon-based defoamer is the acetylenic glycols (7), such as 2,4,7,9-tetramethyl-5-decyne-4,7-diol which are widely used in water-based coatings, agricultural chemicals, and other areas where excellent wetting is needed. 

Trees, especially conifers, contain tall oils. Tall oil is not isolated dkecfly tall oil fatty acids are isolated from the soaps generated as a by-product of the sulfate pulping process for making paper. Refined tall oil fatty acids are obtained by acidification of the soaps, followed by fractional distillation to separate the fatty acids from the rosin acids and terpene hydrocarbons that also are present in the cmde tall oil fatty acids (see Carboxylic acids Fatty ACIDS FROMTALL OIL). 

Rosin and tall oil-based tackifiers are derived from feedstock, which is typically obtained by extraction and distillation of the materials from shredded tree stumps or wood chips. A typical structure of one of the different products obtained through this process is this abietic acid structure shown in Fig. 14 as a representative of the rosin acid family. 

Extraction of rosin. Rosin resins are produced from three types of rosin, i.e. gum, tall oil, and wood. Extensive details about rosin resins extraction and derivatization can be found on page 269 in the book edited by Zinkel and Russell [18]. 

Tall oil rosin is obtained from crude tall oil obtained from the Kraft (sulphate) pulping of various coniferous trees in the paper manufacturing industry. During the Kraft pulping process the fatty acids and the resin acids from the coniferous wood are saponified by the alkaline medium. On concentration of the resulting pulping liquor, the sodium soap of these mixed acids rises to the surface from where they are skimmed out. By acidification of this material with sulphuric acid, the crude tall oil is obtained. Fractional steam distillation of the crude tall oil allows the separation of the tall oil fatty acids and the tall oil rosins [21]. 

Chemistry of rosin. All three types of rosin consist primarily of C20 mono-carboxylic diterpene resin acids, the most common of which have the molecular formula C20H20O2. In addition, rosins contain small amounts of neutral and other acidic components (e.g. fatty acids in tall oil rosin). The neutral components of rosins are diterpene alcohols, hydrocarbons and aldehydes, and their contents generally vary between 5 and 15 wt%. 

The resin acids found in rosins are generally of the abietic- and pimaric-type. Rosins of various pine species differ in their content of abietic vs. pimaric-type acids. Rosins from species exhibiting high abietic-type acid compositions are preferred for production of rosin derivatives. However, the differences in properties of rosins are often associated with their non-resin acid content instead of their chemical compositions. On the other hand, the compositions of rosins from different sources greatly differ [22]. Table 8 shows a typical distribution of resin acids in rosins obtained from gum, tall oil and wood sources. 

Resin acid Tall oil rosin Wood rosin Gum rosin... 

Odour. This aspect is important in resins derived from natural sources. Rosins based on wood and gum rosin retain trace quantities of terpenes and have a piney odour. Tall oil rosins retain the typical sour odour of the rosin. Odour can be removed by steam sparging under vacuum before or during esterification of rosins. Addition of odour masks can also be done. 

Tackifiers. The tackifiers usually are hydrocarbon resins (aliphatic C5, aromatic C9) or natural resins (polyterpenes, rosin and rosin derivates, tall oil rosin ester). They improve hot tack, wetting characteristics and open time and enhance adhesion. The content on tackifiers in a hot melt can be in the region of 10-25%. 

Separation of fatty acids (Ruthven, 1997). Tall oil from the pulp and paper industry is subjected to separation of rosin acid, linoleic acid, oleic acid, and neutral compounds. Distillation at reduced pressure is u.sed, but this leads to degradation of products. A Sorbex process eliminates this problem. 

We focused our attention on Tall oil, a by-product of the paper industry, whenever this is prepared according to the KRAFT process. Said material consists of a mixture of highly unsaturated fatty acids (many of which with conjugated diene systems) and terpene derived rosin acids. The rosin acids have the molecular formula C20H30O2 and thus belong to the diterpenes (pimaric and abietic acids). Tall Oil has an iodine number equal to approximately 170 gl2/100 g. 

During the kraft pulping process, the first step in making hundreds of paper products, crude tall oil is obtained from the alkaline material by acidifying it with sulfuric acid. The crude tall oil is then converted through dehydration, dry distillation, and finally the fractionation of the vaporized tall oil compounds. Fatty acids, rosin acids, and neutral materials make up tall oil. 

Examples of the fatty acids are oleic (c -9-octadecenoic) and linoleic (c ,c -9,12-octadecadienoic) acid. The major constituent of rosin acids is abietic acid. Uses of tall oil are tall oil rosin (31%, for paper size, protective coatings, adhesives, inks, and rubber), tall oil fatty acids (30%, in protective coatings, soaps, and inks), tall oil pitch (30%, in fuel, binders, coatings, rubber modifiers, asphalt, sizing, inks, and hardboard impregnation), and distilled tall oil (9%, in soaps, coatings, flotation, and board impregnation). 

---