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Correlations between the microscopic and chemical changes in wood during peatification and early coalification: a canonical variant study

1989; Elsevier BV; Volume: 13; Issue: 1-4 Linguagem: Inglês

10.1016/0166-5162(89)90089-x

1872-7840

Scott A. Stour, W. Spackman, Jaap J. Boon, Piet G. Kistemaker, D.F. Bensley,

Coal Properties and Utilization

The microscopic and chemical evolution of wood from peats and lignites were investigated in order to achieve a better understanding of the processes associated with the origin of cell-wall-derived huminite macerals in low-rank coals and the relationships between maceral appearance and maceral chemistry. Correlations between the observed microscopic and chemical trends were determined using canomical correlation analyses. These analyses showed that: (1) the birefringence intensity displayed by huminite macerals and pre-macerals generally decreases during peatification and early coalification as their carbohydrate fractions become progressively depolymerized and hydrolyzed (primarily through the action of microbial and fungal enzymes); (2) the intrinsic color of cells walls becomes progressively during peatification and early coalification as the phenolic components of lignins become increasingly dominant and oxidized; and (3) the primary fluorescence intensity of huminite macerals and pre-macerals decreases during peatification and early coalification due to changes in their electronic configurations arising from the partial depolymerization and side-chain modification of the lignin-derived polymers that comprise them. Similarly, changes in the general spectral fluorescence distribution of huminites and pre-huminites (for example the peak wavelength and Q ratio), are also broadly correlated with the aforementioned lignin modifications.