PMID- 12018244
OWN - NLM
STAT- MEDLINE
DCOM- 20021106
LR  - 20190910
IS  - 0273-2289 (Print)
IS  - 0273-2289 (Linking)
VI  - 98-100
DP  - 2002 Spring
TI  - Effects of operating parameters on countercurrent extraction of hemicellulosic 
      sugars from pretreated softwood.
PG  - 147-59
AB  - In a previous study using a continuous countercurrent screw extractor for 
      two-stage dilute-acid hydrolysis, which was focused on the effects of 
      liquid-to-insoluble solids (L/IS) ratio, we demonstrated that by using low 
      volumes of wash water soluble sugars can be recovered from first-stage pretreated 
      softwood at high yields and also at high sugar concentrations. In this study, we 
      investigated the effects of important operating parameters other than the L/IS 
      ratio, such as the feed rates of water and pretreated biomass and the extractor 
      inclined angle, on the performance of the extractor using first-stage pretreated 
      softwood. As biomass and water feed rates increased at the same L/IS ratio, the 
      recovery yield of soluble sugars decreased, probably owing to a reduced solids 
      residence time in the extractor, which is related to the solid/liquid contact 
      time. The sugar recovery yield was higher at a higher extractor inclined angle. 
      This may be attributed to the effects of increased back mixing and a longer 
      residence time for solids at a higher extractor angle. Countercurrent extraction 
      was also carried out with other pretreated biomass having smaller particle sizes 
      and poor drainage rates. The countercurrent screw extractor was found to be 
      unsuitable for these fine materials due to the slow liquid drainage rate and 
      filter-clogging problems. In a test for stability of soluble sugars in 
      first-stage softwood hydrolysate, irrespective of the storage temperature and 
      storage form, the sugar concentration slowly decreased with storage time. 
      However, storage in slurry form showed higher sugar stability compared with that 
      in liquor form at the same conditions.
FAU - Kim, Kyoung Heon
AU  - Kim KH
AD  - National Renewable Energy Laboratory, Golden, CO 80401-3393, USA.
FAU - Tucker, Melvin P
AU  - Tucker MP
FAU - Nguyen, Quang A
AU  - Nguyen QA
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - United States
TA  - Appl Biochem Biotechnol
JT  - Applied biochemistry and biotechnology
JID - 8208561
RN  - 0 (Carbohydrates)
RN  - 0 (Polysaccharides)
RN  - 8024-50-8 (hemicellulose)
SB  - IM
MH  - *Biomass
MH  - Biotechnology/methods
MH  - Carbohydrates/*isolation & purification
MH  - Countercurrent Distribution/methods
MH  - Drug Stability
MH  - Hydrolysis
MH  - Pinaceae/chemistry
MH  - Pinus/chemistry
MH  - Polysaccharides/*chemistry/isolation & purification
MH  - *Wood
EDAT- 2002/05/23 10:00
MHDA- 2002/11/26 04:00
CRDT- 2002/05/23 10:00
PHST- 2002/05/23 10:00 [pubmed]
PHST- 2002/11/26 04:00 [medline]
PHST- 2002/05/23 10:00 [entrez]
AID - 10.1385/abab:98-100:1-9:147 [doi]
PST - ppublish
SO  - Appl Biochem Biotechnol. 2002 Spring;98-100:147-59. doi: 
      10.1385/abab:98-100:1-9:147.