Encimska esterifikacija mlečne kisline v ionskih topilih pri konvencionalnih in nekonvencionalnih pogojih

diplomsko delo univerzitetnega študijskega programa

Andreja Dobaj (Author), Maja Leitgeb (Mentor), Mateja Primožič (Co-mentor)

Abstract

V diplomskem delu je opisana encimska esterifikacija v ionskih toplih pri kontrolirani vsebnosti vode pod konvencionalnimi pogoji (stresalni inkubator, tip GLF 3031) in nekonvencionalnimi pogoji (mikrovalovni sistem, model BenchMate ) segrevanja. Pri predhodno določeni reakcijski mešanici (etanol ali butanol, mlečna kislina, encim Candida antarctica lipaze B — CALB, ionska tekočina Cyphos 202 ali Cyphos 201) smo spreminjali dva procesna parametra, temperaturo in začetno vsebnost vode, tako da smo dobili najvišjo presnovo reakcije pri določen parametru. Na osnovi eksperimentalnih podatkov smo prišli do spoznanja, da je imelo mikrovalovno segrevanje precej bolj ugoden vpliv na encimsko esterifikacijo mlečne kisline in alkohola v ionski tekočini kot konvencionalno segrevanje. Ugotovili smo, da so mikrovalovni žarki povzročili hidrolizo laktilnega estra mlečne kisline (dimer mlečne kisline) med reakcijo, zato je bilo med reakcijo na razpolago več mlečne kisline, kar je posledično povzročilo tudi višje presnove reakcije. Dodajanje ali odvzemanje vode je znižalo presnovo reakcije pri optimalni temperaturi, T = 60ËšC.

Keywords

conventional heating;unconventional heating;biocatalysts ionic liquid;controlled water content;ethyl and butyl lactic ester;

Data

Language:	English
Year of publishing:	2010
Source:	Maribor
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[A. Dobaj]
UDC:	547.473:577.15(043.2)
COBISS:	14996246
Views:	2359
Downloads:	193
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Slovenian
Secondary title:	Enzymatic esterification of lactic acid in ionic liquid under conventional and unconventional conditions
Secondary abstract:	In this diploma work enzymatic esterification in ionic liquid at controlled water content under conventional conditions (shaking incubator, type GLF 3031) and unconventional conditions (microwave system, model BenchMate) of heating is described. The reaction mixture was previously determined (ethanol or buthanol, lactic acid, enzyme Candida antarctica lipase B-CALB, ionic liquid Cyphros 202 and Cyphros 201). We defined (determined) two process parameters, temperature and initial water content, that gave maximal yield in fixed parameter. From the experimental data we recognised, that microwave heating had better impact on enzymatic esterification with alcohol and lactic acid in ionic liquid at controlled water content in the comparison with conventional heating. We found out that microwave irradiation caused lactic ester hydrolysis (dymer of lactic acid) during reaction, thus more monomer of lactic acid were available and as a result we got higher reaction yields. Addition to or removal water from the reaction mixture cased lower reaction yields at optimal temperature, T = 60˚C.
Secondary keywords:	konvencionalni način segrevanja;nekonvencionalni način segrevanja;biokataliza v ionskih topilih;kontrolirana vsebnost vode;etilni in butilni ester mlečne kisline;
URN:	URN:SI:UM:
Type (COBISS):	Undergraduate thesis
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	69 f.
Keywords (UDC):	mathematics;natural sciences;naravoslovne vede;matematika;chemistry;crystallography;mineralogy;kemija;organic chemistry;organska kemija;mathematics;natural sciences;naravoslovne vede;matematika;biological sciences in general;biologija;material bases of life;biochemistry;molecular biology;biophysics;biokemija;molekularna biologija;biofizika;
ID:	1012490