Lignin Lignosulfonates

The majority of the material in sulfite spent liquors originates from lignin (lignosulfonates) and hemicelluloses (Tables 7-5 and 10-1). A variety of useful products can be isolated and prepared from these liquors (Table 10.-2)... 

Kraft, soda, organosolv lignins Lignosulfonates Milled wood lignins Lignin model compounds Dimethylformamide, 2-methoxyethanol/water (8 2, v/v) Water, ethanol/water (2 8, v/v) Dimethylformamide, ethanol/water (8 2, v/v), 2-methoxyethanol/water (8 2, v/v) Water, cyclohexane, ethanol, 2-methoxyethanol/water (8 2, v/v)... 

Around the same time, Mansmann and coworkers reported the production of carbon fibers from a variety of dry-spun materials, including lignin (lignosulfonates) by the simple addition of small amounts of PEO or acrylic acid-acrylamide copolymers. Although similar to the procedure of Ohtani, Mansmann employed acidic rather than neutral and/or alkaline spinning conditions. 

MeadWestvaco USA Non-sulfonated kraft lignin, lignosulfonates Lignin products hydroxymethylated lignin, propoxylated lignin polyols additives for cements and animal feeds Adhesives for particle boards Wax emulsifier Dispersants for dyes and pigments, ceramics, refractories and concrete... 

Asian Lignin Manufacturing India Pvt. Ltd. India Lignin lignosulfonate Binders—phenolic resin type for plywood, foundry sands... 

Many of the chemical reactions used to modify lignosulfonates are also used to modify kraft lignins. These include ozonation, alkaline—air oxidation, condensation with formaldehyde and carboxylation with chloroacetic acid (100), and epoxysuccinate (101). In addition, cationic kraft lignins can be prepared by reaction with glycidjiamine (102). 

The physical and chemical properties of kraft lignin differ greatly from those of lignosulfonates. A summary of these differences is presented in Table 11. 

Lignin sulfonates (lignosulfonates), which are also sludge conditioners. 

Lignins are most usually employed as various types of sodium lig-nosulfonate and are products of sulfite pulping. (Kraft lignins from the Kraft pulping process are also available.) They are used as dispersants, binders, sequestrants, and emulsifiers. Sodium lignosulfonate product variables include color, MW, and the degree of carboxylation and sulfonation on the lignin backbone. 

The use of the lignin fraction is much more cumbersome currently the best-known chemical of a real commercial importance is vanillin, which is obtained by oxidation of the black liquor. Another example is a product called spray-dried lignosulfonate (as sodium salt) obtained from the older, acidic sulfite pulping process. It is sold as a commercial product primarily as a concrete additive for enhanced strength. Since the cement industry is one of the big contributors of carbon dioxide emissions (due to the production of calcium oxide from calcium carbonate), the use of this renewable, wood-derived product not only is fossil-carbon neutral in itself but also reduces carbon dioxide emission due to the diminished need for cement in large infrastructures made of concrete. 

Polyphenolic materials prepared from a polyphenolic material (humic acids, lignosulfonic acid, lignins, phenolic condensates, tannins) and phosphatides (lecithin) - [407]... 

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