AUTOHYDROLYSIS OF HARDWOODS 2
Autohydrolysis of Hardwoods
This article from Elsevier explores the kinetics as well as mechanisms involved in the
autohydrolysis of the hardwoods. The process of autohydrolysis uses water and is a promising technology
especially in the extraction of hemicellulose from the hardwoods before production of pulp (pulping). The
autohydrolysis process produces pulp alongside other vital co-products such as acetic acid and ethanol.
This article explains the process used in performing kinetic and mechanism analysis for autohydrolysis
using the continuous mix flow reactor. The article contrasts its analysis with the previous work by other
researchers who have been using the batch reactors in the analysis of the kinetics and mechanisms in
autohydrolysis. In the study by (Lawoko & Heiningen, 2010) the hardwood chips are reserved in the
basket secured in the reactor. The study used a well-modeled reactor that was efficient in determining the
intrinsic kinetics of the hemicellulose dissolution. The reactor allowed a quick elimination of the
dissolved products. Therefore, there are minimal chances of the degradation as well as further
hemicellulose hydrolysis inside the solution. The rate of xylan removal assumes an S-shaped pattern. The
GPC analysis for the constant extract elimination shows that dissolved xylan oligomers (Lawoko &
Heiningen, 2010) indicates a lesser DP than nearly 25. The lignin withouth xylan oligomers, as well as
the oligomers of cellulose, constitute the main composition in the dissolved materials at the initial
autohydrolysis stage. However, the xylan-lignin (covalently bonded) makes the major compound
eliminated during the later autohydrolysis stage. The molecular weight of the dissolved compounds
reduces with time during the 2nd autohydrolysis stage.
There has been an increase in the price of the fuel all over the world. The biofuels have been
perceived as one of the most promising solutions to the fuel and energy crisis. However, the conversion of
woody biomass into usable biofuel has been regarded as one of the most challenging issues. Mainly, the
conversion of the structural polysaccharides into fermentable simple sugars (monosaccharides) has been
quoted as the major challenge. The autohydrolysis technique gives a glimpse to the promising technology
for cheaper, safe and efficient production of biofuel as well as the pulp. In the process, the only solvent
