Lignin Lignites

A polymeric composition for reducing fluid loss in drilling muds and well cement compositions is obtained by the free radical-initiated polymerization of a water-soluble vinyl monomer in an aqueous suspension of lignin, modified lignins, lignite, brown coal, and modified brown coal [705,1847]. The vinyl monomers can be methacrylic acid, methacrylamide, hydroxyethyl acrylate, hydroxypropyl acrylate, vinylacetate, methyl vinyl ether, ethyl vinyl ether, N-methylmethacrylamide, N,N-dimethylmethacrylamide, vinyl sulfonate, and additional AMPS. In this process a grafting process to the coals by chain transfer may occur. 

Wondrack, L. Szanto, M., and Wood, W. A., Depolymerization of Water-Soluble Coal Polymer from Subbituminous Coal and Lignite by Lignin Peroxidase. Applied Biochemistry and Biotechnology, 1989. 20-1 pp. 765-780. 

Moscow wood is more similar to coalified wood of subbituminous rank than it is of coalified wood of lignite rank, assuming that its lignin was originally similar to lignin in Cretaceous or younger woods. 

The analysis of lignitic woods by analytical pyrolysis has shown that lignin structural units can be preserved as biomaikers in samples as old as Carboniferous age, or approximately 300 million years. At least half or more of the pyrolysis products in lignitic wood of Cretaceous age are methoxyphenols characteristic of lignin. The pn uct distributions in these Cretaceous samples indicate that the lignin is mainly altered in the 3-carbon side chains. Phenols, cresols, catechols, and other methylated phenols account for most of the remaining pyrolysis products. It is likely diat these products are also derived frx>m li in, especially lignin that has been altered by coalification reactions. 

Lavoisier s method of determining the heat developed by oomboation, 03L lead and zinc, peculiarity lu expansion, 4. Leslie s experiments on radiant heat, 12. lignin, 30,31, lignite. 74,110. 

B. K. Mazumdar. Low rank coals like lignites and natural humic acid derived from such coals are known to contain alicyclic structures in their constitution. How does the author envisage the formation of such structures in the transformation of lignin to humic acid-like substances ... 

In addition, the parenchymatous cells in the xylem appear to yield at least two lignitic materials. One is a dark red-brown material that may be derived from inclusions originally present in the cell. This material is common and may be observed in Figures 2, 3, 5, 6, 7, and 8. The other coalified product associated with this cell type is yellowish in color and derived from the wall of the cell (Figures 2 and 6). Ray parenchyma and longitudinal xylem parenchyma typically form only a primary wall, and usually the wall is devoid of lignin. It is of interest that this wall layer is preserved and that it is frequently possible to observe the simple pits that are characteristic of this cell type (Figure 2). 

Generally, the starting materials used in the commercial production of activated carbons are those with high carbon content, such as wood, lignite, peat, and coal of different ranks [175,176], But, over the last years, growing interest has now shifted to the use of other low-cost, and abundantly accessible, agricultural byproducts, such as coconut shells, rockrose, eucalyptus kraft, lignin, apricot stone, cherry stone, and olive stone to be converted into activated carbons [176],... 

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