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Title: Effects of crystallinity on dilute acid hydrolysis of cellulose by cellulose ball-milling study

Abstract

The dilute acid (0.05 M H 2SO 4) hydrolysis at 175°C of samples comprising varying fractions of crystalline (α-form) and amorphous cellulose was studied. The amorphous content, based on XRD and NMR, and then the product (glucose) yield, based on HPLC, increased by as much as a factor of three upon ball milling. These results are interpreted in terms of a model involving mechanical disruption of crystallinity by breaking hydrogen bonds in α-cellulose, opening up the structure and making more β-1,4 glycosidic bonds readily accessible to the dilute acid. In parallel with hydrolysis to form liquid phase products, there are reactions of amorphous cellulose that form solid degradation products.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
878262
Report Number(s):
PNNL-SA-46829
Journal ID: ISSN 0887-0624; ENFUEM; 16691; 16307; TRN: US200611%%57
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Energy and Fuels; Journal Volume: 20; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; ACID HYDROLYSIS; CELLULOSE; GLUCOSE; HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY; HYDROGEN; HYDROLYSIS; MILLING; OPENINGS; X-RAY DIFFRACTION; Environmental Molecular Sciences Laboratory

Citation Formats

Zhao, Haibo, Kwak, Ja Hun, Wang, Yong, Franz, James A., White, John M., and Holladay, Johnathan E. Effects of crystallinity on dilute acid hydrolysis of cellulose by cellulose ball-milling study. United States: N. p., 2005. Web. doi:10.1021/ef050319a.
Zhao, Haibo, Kwak, Ja Hun, Wang, Yong, Franz, James A., White, John M., & Holladay, Johnathan E. Effects of crystallinity on dilute acid hydrolysis of cellulose by cellulose ball-milling study. United States. doi:10.1021/ef050319a.
Zhao, Haibo, Kwak, Ja Hun, Wang, Yong, Franz, James A., White, John M., and Holladay, Johnathan E. Fri . "Effects of crystallinity on dilute acid hydrolysis of cellulose by cellulose ball-milling study". United States. doi:10.1021/ef050319a.
@article{osti_878262,
title = {Effects of crystallinity on dilute acid hydrolysis of cellulose by cellulose ball-milling study},
author = {Zhao, Haibo and Kwak, Ja Hun and Wang, Yong and Franz, James A. and White, John M. and Holladay, Johnathan E.},
abstractNote = {The dilute acid (0.05 M H2SO4) hydrolysis at 175°C of samples comprising varying fractions of crystalline (α-form) and amorphous cellulose was studied. The amorphous content, based on XRD and NMR, and then the product (glucose) yield, based on HPLC, increased by as much as a factor of three upon ball milling. These results are interpreted in terms of a model involving mechanical disruption of crystallinity by breaking hydrogen bonds in α-cellulose, opening up the structure and making more β-1,4 glycosidic bonds readily accessible to the dilute acid. In parallel with hydrolysis to form liquid phase products, there are reactions of amorphous cellulose that form solid degradation products.},
doi = {10.1021/ef050319a},
journal = {Energy and Fuels},
number = 2,
volume = 20,
place = {United States},
year = {Fri Dec 23 00:00:00 EST 2005},
month = {Fri Dec 23 00:00:00 EST 2005}
}
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