TY - JOUR
T1 - Design of a continous process for the production of highly substituted granular carboxymethyl starch
AU - Tijsen, C. J.
AU - Voncken, R. M.
AU - Beenackers, A. A. C. M.
N1 - Cited By (since 1996): 7
PY - 2001/1
Y1 - 2001/1
N2 - A process design for the continuous production of highly substituted granular carboxymethyl starch (CMS) from potato starch is presented. Experiments in a batch reactor showed that aqueous isopropyl alcohol (IPA) is the optimal reaction medium to prevent the substituted starch from swelling and to keep it in a granular form. The degree of substitution (DS) that can be obtained in a single reaction step is limited to about 1.3. It is possible to increase the DS in a consecutive batch reaction where a lower water concentration is used. The continuous process consists of two continuous stirred tank reactors in series, each with a specific H2O/IPA ratio. For a complete recycling of the organic reaction medium a hybrid dehydration section is evaluated. Based on this design, granular carboxymethyl potato starch with a DS of 1.5 or higher can be produced continuously. For an annual production of 3600 tons of CMS, the first CSTR should have: a starch content of 20% (w/w); a H2O/IPA ratio of ; a temperature of 40°C; a volume of ; and a residence time of . To increase the DS to 1.5, the intermediate CMS, with a DS of 0.8, is fed to the second CSTR, having a starch content of 20% (w/w); a H2O/IPA ratio of ; a temperature of 40°C; a volume of ; and a residence time of .
AB - A process design for the continuous production of highly substituted granular carboxymethyl starch (CMS) from potato starch is presented. Experiments in a batch reactor showed that aqueous isopropyl alcohol (IPA) is the optimal reaction medium to prevent the substituted starch from swelling and to keep it in a granular form. The degree of substitution (DS) that can be obtained in a single reaction step is limited to about 1.3. It is possible to increase the DS in a consecutive batch reaction where a lower water concentration is used. The continuous process consists of two continuous stirred tank reactors in series, each with a specific H2O/IPA ratio. For a complete recycling of the organic reaction medium a hybrid dehydration section is evaluated. Based on this design, granular carboxymethyl potato starch with a DS of 1.5 or higher can be produced continuously. For an annual production of 3600 tons of CMS, the first CSTR should have: a starch content of 20% (w/w); a H2O/IPA ratio of ; a temperature of 40°C; a volume of ; and a residence time of . To increase the DS to 1.5, the intermediate CMS, with a DS of 0.8, is fed to the second CSTR, having a starch content of 20% (w/w); a H2O/IPA ratio of ; a temperature of 40°C; a volume of ; and a residence time of .
U2 - 10.1016/s0009-2509(00)00243-8
DO - 10.1016/s0009-2509(00)00243-8
M3 - Article
VL - 56
SP - 411
EP - 418
JO - Chemical Engineering Science
JF - Chemical Engineering Science
IS - 2
ER -