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33-465: This park is a protected area for the quebracho trees . Forests of quebracho colorado chaqueño ( Schinopsis balansae ) were once located in the north of Santa Fe and the western half of Chaco, and had entered the northeast region of the province of Corrientes . Its strong wood and its abundant tannin caused it to be over-exploited for a century. The area harbors several environments: scrubland , savanna , swamps , and small lakes. The scrubland

66-593: A French tanner, Emilio Poisier, who lived in Argentina. By 1895, the quebracho extracts were exported to Europe and became the principal vegetal tannin source in the world. Amongst other activities Ernesto Tornquist (1842–1908) organised the exploitation of quebracho in Santiago del Estero , in the Chaco region. Originally a dry forest area, the abundance of quebracho attracted timber industries of British capital during

99-464: A Swedish engineer patented a process of ethanol generation from the residual 2-2.5% fermentable hexose sugars in the spent liquor. The sulfite process can use calcium , ammonium , magnesium or sodium as a base. The sulfite process is acidic and one of the drawbacks is that the acidic conditions hydrolyze some of the cellulose, which means that sulfite pulp fibers are not as strong as kraft pulp fibers. The yield of pulp (based on wood used)

132-453: A decade later in 1874 the first commercial sulfite pulp mill was built in Sweden . It used magnesium as the counter ion and was based on work by Carl Daniel Ekman . By 1900 sulfite pulping had become the dominant means of producing wood pulp, surpassing mechanical pulping methods. The competing chemical pulping process, the sulfate or kraft process was developed by Carl F. Dahl in 1879 and

165-430: A desirable alternative to consider comparatively because they are much less expensive to produce than grape tannins. Myo-inositol and arabitol are detected in tannins from quebracho. Researches are being made to develop an eco-friendly anti- biofouling paint from quebracho tannin. The tannic acid , in the form of alkalized salts, was extensively used as a deflocculant in drilling muds in 1940s-1950s, until it

198-402: A very hard, durable timber . Quebracho is sometimes used as a commercial name for the tannin derived from the trees or their timber. A further species, Jodina rhombifolia (Syn. Iodinia rhombifolia , the quebracho flojo (the loose, soft quebracho) or quebrachillo , quebrachillo flojo and sombra de toro , sombra de toro macho , quinchilin , quinchirin , of the family Santalaceae ,

231-533: A wide range of everyday products from adhesives to baked goods to pharmaceuticals . Sulfite pulping is generally less destructive than kraft pulping, so there are more usable byproducts. Chief among sulfite process byproducts are lignosulfonates , which find a wide variety of uses where a relatively inexpensive agent is needed to make a water dispersion of a water-insoluble material. Lignosulfonates are used in tanning leather, making concrete , drilling mud , drywall and so on. Oxidation of lignosulfonates

264-484: A wide variety of cellulose derivatives, for example rayon , cellophane , cellulose acetate and methylcellulose . Rayon is a reconstituted cellulose fiber used to make many fabrics. Cellophane is a clear reconstituted cellulose film used in wrapping and windows in envelopes. Cellulose acetate was used to make flexible films for photographic use, computer tapes and so on and also to make fibers. Methylcellulose and other cellulose ether derivatives are used in

297-551: Is a common name in Spanish to describe very hard (density 0.9–1.3) wood tree species. The etymology of the name derived from quiebrahacha , or quebrar hacha , meaning " axe -breaker". The corresponding English-language term for such hardwoods is breakax or breakaxe . There are at least three similar commercially important tree species that grow in the Gran Chaco region of South America. These species provide tannin and

330-500: Is also sometimes mentioned. Other species with less economic significance are also locally known as quebracho or as quebrachillo or quebrachilla and could be found in other areas of Latin America ;: as false quebracho or quebracho falso Quebracho wood from Schinopsis spp is red-colored and very hard. Other names for the wood are: Quebracho produces tannins that can be extracted in quebracho sawmills from

363-406: Is higher than for kraft pulping and sulfite pulp is easier to bleach . Sulfite pulp remains an important commodity , especially for specialty papers and as a source of cellulose for non-paper applications. It is used to make fine paper , tissue , glassine , and to add strength to newsprint . A special grade of bleached sulfite pulp is known as dissolving pulp which is the raw material for

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396-635: Is less environmentally costly. The use of wood to make pulp for paper began with the development of mechanical pulping in the 1840s by Charles Fenerty in Nova Scotia and by F. G. Keller in Germany . Chemical processes quickly followed, first with Julius Roth 's use of sulfurous acid to treat wood in 1857, followed by Benjamin Chew Tilghman 's US patent on the use of calcium bisulfite , Ca(HSO 3 ) 2 , to pulp wood in 1867. Almost

429-550: Is no "lime cycle". The process is conducted in large pressure vessels called digesters. Sulfite pulping is carried out between pH 1.5 and 5. The pulp is in contact with the pulping chemicals for 4 to 14 hours and at temperatures ranging from 130 to 160 °C (266 to 320 °F ), again depending on the chemicals used. Most of the intermediates involved in delignification in sulfite pulping are resonance-stabilized carbocations formed either by protonation of carbon-carbon double bonds or acidic cleavage of ether bonds which connect many of

462-413: Is recovered in a wet scrubber to give a slurry of magnesium hydroxide . This magnesium hydroxide slurry is then used in another scrubber to absorb sulfur dioxide from the flue gases producing a magnesium bisulfite solution that is clarified, filtered and used as the pulping liquor. Sodium-based processes use a recovery system similar to that used in the kraft recovery process , except that there

495-452: Is rich in profisetinidins and prorobinetidins . The expected masses found in mass spectrometry in negative mode in quebracho tannin are 289, 561, 833, 951, 1105, 1377, 1393, 1651 and 1667. In Quebracho colorado, the sugars and the lignins are thought to be covalently linked to the condensed tannins. Quebracho tannin is also sold as an enological tannin . The quebracho tannins structure is very similar to that of grape tannins, making them

528-489: Is the habitat of the red quebracho ( Schinopsis lorentzii ), white quebracho ( Aspidosperma quebracho-blanco ), algarrobo ( Prosopis alba ), and lapacho ( Tabebuia spp.), all of which are commercially valuable species. The fauna includes large predators such as cougars . In the lakes one finds yacare caimans and capybaras . Elsewhere there are armadillos , South American tapirs and plains viscachas , as well as birds (more than 340 species). The fauna also includes

561-450: Is usually called brown liquor, but the terms red liquor, thick liquor and sulfite liquor are also used (compared to black liquor in the kraft process ). Pulp washers, using countercurrent flow, remove the spent cooking chemicals and degraded lignin and hemicellulose. The extracted brown liquor is concentrated, in multiple effect evaporators . The concentrated brown liquor can be burned in the recovery boiler to generate steam and recover

594-510: The hydrolysable tannins and gallic acid found in the sapwood constitute the raw material for the biosynthesis of the condensed tannins found in the heartwood . Fustin (predominantly (-)-Fustin 66%), (-)-7:3':4'-trihydroxyflavan-3:4-diol ((-)- leuco-fisetinidin ), (+)- catechin , gallic acid, fisetin and 2-benzyl-2-hydroxycoumaran-3-ones have been isolated from the heartwoods of Schinopsis balansae , Schinopsis quebrachocolorado and from commercial quebracho extract. Quebracho tannin

627-401: The 19th century, leading to extensive deforestation . This devastated the ecosystem in a relatively short time. The private owners of the Chaco then turned to cotton production, employing the local Toba people as a cheap seasonal workforce; the conditions did not change substantially for decades. The British-owned Central Argentine Railway reached the city of Santiago del Estero in 1884 and

660-533: The black howler monkey ( Alouatta caraya ). Indigenous communities of the Mocoví and Toba peoples are found in the protected area. This article about a place in Chaco Province , Argentina is a stub . You can help Misplaced Pages by expanding it . This protected areas-related article is a stub . You can help Misplaced Pages by expanding it . Quebracho tree Quebracho [keˈβɾatʃo]

693-438: The constituents of lignin. It is the latter reaction which is responsible for most lignin degradation in the sulfite process. The electrophilic carbocations react with bisulfite ions (HSO 3 )to give sulfonates. The sulfite process does not degrade lignin to the same extent that the kraft process does and the lignosulfonates from the sulfite process are useful byproducts . The spent cooking liquor from sulfite pulping

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726-698: The first kraft mill started (in Sweden) in 1890. The first sulphite mill in the United States was the Richmond Paper Company in Rumford, Rhode Island in the mid-1880s. The invention of the recovery boiler by G. H. Tomlinson in the early 1930s allowed kraft mills to recycle almost all of their pulping chemicals. This, along with the ability of the kraft process to accept a wider variety of types of wood and produce stronger fibers made

759-417: The heartwood of both red ( Schinopsis lorentzii ) and white quebracho ( Aspidosperma quebracho-blanco ). Logs are inserted into planers to produce chips that are used to produce the quebracho extract by boiling them in vats. It is used for fine leather tanning and imparts a red-brown color. Ordinary or warm soluble quebracho (also known as insoluble Quebracho) is the natural extract obtained directly from

792-456: The inorganic chemicals for reuse in the pulping process or it can be neutralized to recover the useful byproducts of pulping. Recent developments in Chemrec's black liquor gasification process, adapting the technology to use in the sulfite pulping process, could make second generation biofuels production an alternative to the conventional recovery boiler technology. Around 1906 Gösta Ekström

825-733: The kraft process the dominant pulping process starting in the 1940s. Sulfite pulps now account for less than 10% of the total chemical pulp production and the number of sulfite mills continues to decrease. Magnesium was the standard counter ion until calcium replaced it in the 1950s. The pulping liquor for most sulfite mills is generated by treating various bases (alkali metal or alkaline earth hydroxides) with sulfur dioxide: Similar reactions are effected with divalent cations (Mg2+, Ca2+) and using carbonates in place of hydroxide. The ratio of sulfite to bisulfite depends on pH; above pH=7, sulfite predominates. The earliest process used calcium, obtained as inexpensive calcium carbonate , and there

858-462: The lignocellulose. A variety of sulfite/bisulfite salts are used, including sodium (Na ), calcium (Ca ), potassium (K ), magnesium (Mg ), and ammonium (NH 4 ). The lignin is converted to lignosulfonates , which are soluble and can be separated from the cellulose fibers. For the production of cellulose, the sulfite process competes with the Kraft process which produces stronger fibers and

891-582: The ordinary extract to a sulphiting process which transforms the phlobaphenes into completely soluble tannins. The cold soluble quebracho extracts are the most universally known and used types. The chemical structure of these extracts can be described as polymers of epicatechin . The main properties of these extracts are: a very rapid penetration, a high tannin content and a relatively low percentage of non-tannins. The rather low acid and medium salt content characterise them as mild tanning extracts (low astringency). Quebracho tannins give an important added value to

924-401: The pulping chemicals since ammonia or ammonium salts are oxidized to nitrogen and nitrogen oxides when burned. The recovery process used in magnesium-based sulfite pulping the "Magnefite" process is well developed. The concentrated brown liquor is burned in a recovery boiler, producing magnesium oxide and sulfur dioxide , both of which are recovered from the flue gases. Magnesium oxide

957-447: The quality of leathers, such as vacchetta, belts and garments, making them more compact and tear resistant with a pleasant touch. The sulphited quebracho extract may be carcinogenous in mice. Other recent studies show that quebracho tannins present a strong anti-mutagenic activity. The heartwood contains from 20 to 30 percent tannin and 3 or 4 percent water-soluble nontannin. It is said to not ferment. According to King and White (1957),

990-430: The quebracho wood. This type of extract is rich in condensed tannins of natural high molecular weight ( phlobaphenes ), which are not easily soluble. Its use is therefore limited to addition of small amounts during the process of tanning leather intended for shoe soles in hot liquids (temperature above 35 °C) to improve the yield and the water-proofness of the leather. The cold soluble extracts are obtained by subjecting

1023-403: The trees were exported via San Lorenzo port . The quebracho tree is also used to produce hard wood barbecue charcoal. Pictures on flickr Sulfite process The sulfite process produces wood pulp that is almost pure cellulose fibers by treating wood chips with solutions of sulfite and bisulfite ions. These chemicals cleave the bonds between the cellulose and lignin components of

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1056-557: Was little incentive to recover the inorganic materials. At least in Sweden the brown liquor from this process was previously frequently used for producing ethanol, while with other brown liquors the fermentable hexose sugars are left to contribute to the energy needed in the recovery process. Calcium sulfite, which is poorly soluble, converts to calcium bisulfite only at low pH. Therefore calcium-based sulfite processes require acidic conditions. Ammonia-based processes do not allow recovery of

1089-518: Was replaced with lignosulfonates . Its red color gave the mixture the name red mud . Quebracho tannin acts as flocculant agent to remove surfactant as sodium dodecylbenzenesulfonate in water treatment. For its polyphenolic structure, quebracho tannin is widely studied for particle boards , plywood and fiber board gluing. The Argentine companies Unitán and Silvateam are the main leaders in quebracho tannins production. The tanning properties of quebracho extracts were discovered in 1867 by

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