Vanillin manufacture

The process starting from lignin has faced serious problems, such as reduced availabiUty and environmental impact. The availabiUty is reduced because the new process for making paper paste yields less Hquor. As a result, it is likely that the larger companies will not reinvest in new factories to process Hquors to meet demand. The process s environmental impact is also problematic because over 160 t of caustic waste are produced for every ton of vanillin manufactured. 

CaH803. Fine white needles, m.p. 82°C, b.p. 285°C, strong vanilla odour, characteristic taste. It occurs extensively in nature, and is the odoriferous principle of the vanilla pod it can be obtained from the glucoside coniferin. Vanillin is made commercially from the ligno-sulphonic acid obtained as a by-product in the manufacture of wood pulp. It is one of the most important flavouring and perfuming... 

Reduction Products. Glyoxyhc acid [298-12 ], HOOCCHO, mol wt 74.04, is produced as aqueous solution by the electrolytic reduction of oxahc acid. It is used for the manufacture of vanillin. 

The manufacture of vanillin shows the progress made in the chemistry and chemical engineering of the substance. Most commercial vanillin is synthesized from guaiacol the remainder is obtained by processing waste sulfite Hquors. Preparation by oxidation of isoeugenol is of historical interest only. 

Solubility. SolubiUty in water is less than 2% the solubiUty in ethanol is given by the ratio one part vanillin to two parts alcohol. Certain manufacturing processes require that the product be in Hquid form. Depending on the appHcation, the solvent must be chosen in accordance with the manufacturing process and regulation requirements. 

Confections. Main appHcations are sugared almonds, caramel, nougat, and sweets. For sugared almonds and caramel, vanillin is mixed into the sugar in the dry phase of the recipe. For nougat. Vanillin is added during the Hquid phase of manufacturing. In sweets, vanillin is added in the form of a 10% ethanol solution. 

Flavor-Masking Deodorant. In addition to its use as a constituent of perfume compositions, vanillin is also useful as a deodorant to mask the unpleasant odor of many manufactured goods. As a masking agent for numerous types of ill-smelling mass-produced industrial products, particularly those of synthetic mbber, plastics, fiber glass, inks, etc, vanillin finds extensive use. It is often the most inexpensive material for the amount of masking effect it provides. Only traces are required for this purpose as the odor of vanillin is perceptible in dilutions of 2 x 10 mg/m of air. Cmde vanillin is acceptable for such purposes. 

Pharmaceutical Products. Rhc ne-Poulenc offers a flaked technical-grade vanillin, Vaniltek, to be used in pharmaceutical appHcations. The single largest use for vanillin is as a starting material for the manufacture of an antihypertensive dmg having the chemical name of Methyldopa or L-3-(3,4-dihydroxyphenyl)-2-methylalanine. 

For the manufacture of vanillin, eugenol is first isomerised to iso-eugenol, in which a rearrangement in the side chain has taken place. 

Another illustration of the enormous potential of catalytic methodologies in fine chemicals manufacture is the new Rhone-Poulenc process for the flavour ingredient, vanillin (Ratton, 1998). The process involves four steps, all performed with a heterogeneous catalyst, starting from phenol (Fig. 2.37). 

Howard A process for separating lignosulfonates from sulfite liquor from papermaking. The lignosulfonates are precipitated as their calcium salts. The product is used in the manufacture of vanillin. 

Rhovanil fine mesh vanillin, 25 550, 552 Rhovanil free flow vanillin, 25 550 Ribbon silicon, 23 40-41 Ribbon Thermal Shock Test, 21 513 Ribbon-type mixers, 16 719-720 in bar soap manufacture, 22 751 Riboflavin, 25 796-797 Ribonucleic acid probes, 14 153 Ribonucleic acids (RNAs), 12 449 ... 

N,N-dimethylaniline org chem C6H5N(CH3)2 A yellowish liquid slightly soluble in water used in dyes and solvent and In the manufacture of vanillin. Also known as aniline N,N-dimethyl. en en, dT meth-3ran-3 len dimethylbenzene See xylene. dT meth-3rben,zen ... 

Uses Manufacture of vanillin, Michler s ketone, methyl violet, and other dyes solvent reagent for methyl alcohol, hydrogen peroxide, methyl furfural, nitrate, and formaldehyde chemical intermediate stabilizer reagent. 

The chemical and enzymatic oxidative degradation of lignin (and coal) is used to obtain not only vanillin and benzoic acid, but also other aromatics (Baciocchi et al. 1999, references therein). In principle, lignin could be a major nonfossil and renewable source of aromatic compounds, a feedstock for synthesis of useful products. The problem deserves finding new ion-radical routes to cleave lignin. At present, there is some shortage in oil, gas, and even coal, which had usually been well-available natural sources of aromatics. In the near future, biomass may (and must) replace fossil-originated materials in the manufacture of commercial carbon-based products. 

Much research and development for the biotechnological manufacture of vanillin has been done [175]. 

MARATHON-HOWARD PROCESS. A treatment of waste sulfite liquor from sulfite pulp manufacture In recover chemicals and reduce steam pollution. The waste sulfite is treated with line and precipitates. (I) calcium sulfite for use in preparing fresh cooking acid for the sulfite pulp process, and 121 a basic calcium salt tif ligmn sulfonic acid (lignin sullYmalesi that can be pressed and used as a fuel of used as raw- material for vanillin, lignin plasties, and other chemicals. The remaining liquor with its BOD reduced X() ( is the effluent. 

Vanillin is added, in powder form during the manufacturing process of chocolate, in average amounts of 20 g per 100 kg of the finished product. However, this amount varies according to the quality of the chocolate being made. 

Wood forms one of the world s most important chemical raw materials. It is the primary source of cellulose for the pulp and paper and cellulose industries. These industries are well up in the group of 10 major industries of the United Slates. For paper, rayon, films, lacquers, explosives and plastics, which comprise the greatest chemical uses of wood, it is the cellulose component (plus certain amounts of hemicellulose) of wood that is of value. The lignin forms a major industrial waste as a by-product of the paper and cellulose industries. Its major use is in its heat value in the recovery of alkaline pulping chemicals. A variety of minor uses for lignin have been developed, such as for the manufacture of vanillin, adhesives, plastics, oil-well drilling compounds and fillers for rubber. 

Eugenol has been used as a feedstock in the production of isoeugenol, which is needed in the manufacture of vanillin. Methylation of eugenol yields methyleugenol, which acts as a sex attractant for a certain type of fly (Dacus dorsalis) [7,8]. 

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