Lignin and Sugars

PureHemp Technology Lignin and Sugars

The three primary components of hemp stalks are cellulose (50%), lignin (20%) and hemicellulose (20%), making up about 90% by weight of the stocks. When hemp stalks are processed in the CCR, a solid cellulose-rich pulp is produced along with a liquid stream. This liquid stream contains typically over 85% of the lignin and over 90% of the hemicellulose, which started out as solids and once process in the CCR becomes solubilized in the liquid. This liquid stream is further processed by first removing the lignin, leaving a liquid rich in xylose sugar. Xylose is a 5-carbon sugar that is made from the hemicellulose portion of the biomass.

Lignin

Removing lignin from hemp stalks is key to being able to manufacture high-quality pulp for making paper products. Lignin removal occurs continuously in a five-minute process inside the CCR as biomass advances downstream and most of the lignin becomes solubilized in the liquid stream. At this point, the solubilized lignin and xylose travel in the opposite direction and are washed out of the CCR for further recovery. The CCR technology produces a low molecular weight lignin, which is more suitable for formulating into a wide variety of products as compared to conventionally manufactured Kraft or soda lignin generated by the existing pulp and paper industry. Kraft lignin has an average molecular weight of  >60,000 Dalton versus the average molecular weight of CCR lignin <10,000 Dalton. This highly reactive and lower molecular weight CCR lignin has many advantages over Kraft lignin due to the fact that it’s more reactive and can readily react with many more molecules to manufacture products including adhesives, plastics, chemicals and fuels. PureHemp is producing small quantities of its hemp lignin and is selling 1-gram samples. Contact for sample pricing.

Sugars

Hemicellulose fibers are thin chains of 5-carbon molecules that grow in all directions around the thicker and more robust 6-carbon cellulose fibers. Within the CCR under various processing conditions, a controlled amount of the hemicellulose solids are being converted into a soluble oligomeric xylose sugar that, like the lignin, changes direction within the CCR and is washed out within minutes. Once the lignin is removed from the CCR liquid stream, what remains is the third fraction that is rich in oligomeric xylose.  This oligomeric xylose is further refined in another post-CCR unit operation and monomerized to a fermentable xylose sugar-rich fraction, which becomes available as a raw material to manufacture xylitol and a wide variety of other consumer and industrial products.