-
Enzyme catalyzed reactions in dense gasesKnez, Željko ; Leitgeb, Maja ; Krmelj, VlastaDense gases were used as a biochemical reaction medium. Esterification of oleic acid with oleyl alcohol, catalyzed by lipase from Rhizomucor miehei (LipozymeIM) was used as a model system. Due to the ... limitation of the process that may arise from the non-polarity of carbon dioxide, which preferentially dissolves hydrophobic compounds, studies were also performed with other gases (n-butane, n-propane, n-propane/n-butane mixture). The study of the pressure stability of the immobilized lipaze showed that the lipase is quite stable; it does not lose its activity when it is exposed to various dense gases at high pressure for a longer time. Esterification rates at high pressure were determined for all systems, and it was found that they were higher than at atmospheric pressure. The studies of thermodynamic properties and mass transfer were performed in a batch stirred tank reactor in dense carbon dioxide for the esterification of oleic acid with oleyl alcohol (catalyzed by lipase). The highest rate and maximum conversion were determined. It was found that in a continuous fixed bed reactor at 150 bar, 40°C and water activity 0.46% w/w, the activity of the enzyme preparation was practically unchanged when CO2 was used as a solvent. The addition of small amounts of water increases the conversion rate. A higher conversion was also observed at a longer residence time. When n-butane was used as a reaction medium a decrease of conversion was observed.Source: The journal of supercritical fluids. - ISSN 0896-8446 (14, 1998, str. 17-29)Type of material - article, component partPublish date - 1998Language - englishCOBISS.SI-ID - 4108822
Author
Knez, Željko |
Leitgeb, Maja |
Krmelj, Vlasta
Topics
kemijska tehnika |
načrtovanje procesov |
esterifikacija |
encimi |
visoki tlaki |
superkritični fluidi |
termodinamski parametri |
prenos snovi |
chemical engineering |
process design |
esterification |
enzymes |
high pressures |
supercritical fluids |
thermodynamic parameters |
mass transfer
Shelf entry
Permalink
- URL:
Impact factor
Access to the JCR database is permitted only to users from Slovenia. Your current IP address is not on the list of IP addresses with access permission, and authentication with the relevant AAI accout is required.
| Year | Impact factor | Edition | Category | Classification | ||||
|---|---|---|---|---|---|---|---|---|
| JCR | SNIP | JCR | SNIP | JCR | SNIP | JCR | SNIP | |
Impact factor
Select the library membership card:
DRS, in which the journal is indexed
| Database name | Field | Year |
|---|
| Links to authors' personal bibliographies | Links to information on researchers in the SICRIS system |
|---|---|
| Knez, Željko | 02619 |
| Leitgeb, Maja | 00534 |
| Krmelj, Vlasta | 17866 |
Select pickup location:
Material pickup by post
Notification
Subject headings in COBISS General List of Subject Headings
Select pickup location
| Pickup location | Material status | Reservation |
|---|
Please wait a moment.