PRE-HYDROLYSIS OF THE PHENYL GLYCOSIDIC BOND IN A MODEL COMPOUND : Simulation of cleavage in lignin-carbohydrate bond using model compound, phenyl- -D-glucopyranoside

ISBN-13: 9783639193169 / Angielski / Miękka / 2009 / 76 str.

Sagar Deshpande

Opis

The pre-hydrolysis conditions were chosen to simulate different pretreatment methods such as auto hydrolysis, green liquor pretreatment and acid hydrolysis. It was found that hydrolysis of the phenyl-glucoside model compound at near neutral aqueous conditions (pH 6) was minimal (4 %) at 170°C. On the other hand hydrolysis was nearly complete (95 %) at this temperature with the addition of acetic acid at a concentration expected to be generated from deacetylation of xylan in hardwoods(about 10 g/L). At acid conditions of pH 1.65 the temperature may be lowered to 105 or 121 °C while still obtaining a significant (80-90 %) hydrolysis yield.The hydrolysis experiments performed simulating green liquor extraction showed as previously reported that the hydrolysis of phenyl-glucoside produces phenol and levoglucosan while no glucose is formed.The result showed that hydrolysis of the phenyl-glucoside at 155 °C was essentially complete with quantitative formation of levoglucosan and phenol rather than glucose and phenol.

O autorze

Mr. Sagar Deshpande was born in India(1982).He earned his Bachelor''s degree in Chemical Engineering from Mumbai. He came to US in 2006 to pursue his Masters. Currently he works with Sensor Research & Development Corparation, Maine. His expertise is in the field of Testing and Validation of chemical sensors.