ABSTRACT
Information as to how lignin is deposited in wood has been obtained using the technique of ultraviolet microscopy. Despite its general intractability, a number of chemical uses tor lignin have been developed, both by reacting it as a high molecular weight polymer and by converting it to lower molecular weight materials by chemical transformations. Ever since the discovery that lignin can be chemically modified and thereby separated from cellulose, many investigators have studied it both with a view toward establishing its chemical structure and using it as a raw material source for production of organic chemicals. It would appear that pyrolysis and modified pyrolysis procedures have a great potential in processing of lignin to provide useful low molecular weight chemicals. The best procedures will undoubtedly combine pyrolysis with other degradative procedures. An interesting pyrolysis of the lignin in kraft black liquors has been reported.
