Enzyme-catalyzed reactions in different types of high-pressure enzymatic reactors

Abstract

The enzyme-catalyzed hydrolysis of carboxy-methyl cellulose (CMC) was performed in three different types of reactors; in a batch stirred-tank reactor (BSTR) operating at atmospheric pressure, in a high-pressure batch stirred-tank reactor (HP BSTR) and in a high-pressure continuous tubular-membrane reactor (HP CTMR). In the high-pressure reactors aqueous SC CO2 was used as the reaction medium. The aim of our research was optimization of the reaction parameters for reaction performance. All the reactions were catalyzed by cellulase from Humicola insolens. Glucose production in the high-pressure batch stirred-tank reactor was faster than in the BSTR at atmospheric pressure. The optimal temperature for the reaction performed in the BSTR at atmospheric pressure was 30?C, while the optimal temperature for the reaction performed in SC CO2 was 32?C. The influence of the application of tubular ceramic membranes in the high-pressure reaction system was studied on the model reaction of CMC hydrolysis at atmospheric pressure and in SC CO2. The reaction was catalyzed by cellulase from Humicola insolens covalently linked to the surface of the ceramic membrane. The hydrolysis of CMC in SC CO2 and at atmospheric pressure was performed for a long time period. The reaction carried out in SC CO2 was more productive than the reaction performed at atmospheric pressure.Ispitivana je enzimski katalizovana hidroliza karboksimetil celuloze (CMC) u tri razlicita tipa reaktora: sarznom reaktoru pod atmosferskim pritiskom (BSTR) l visokim pritiskom (HP BSTR) kao i u cevnom membranskom reaktoru pod visokim pritiskom (HP CTMR). U reaktorima koji su radili pod visokim pritiscima koriscena je voda i natkriticni ugljen dioksid (SC CO2) kao reakcioni medijum. Cilj ovih ispitivanja bio je da se optimizuju reakcioni uslovi za ovu reakciju. Svi eksperimenti su realizovani koriscenjem enzima celulaze Humicola insolens. Dobijanje glukoze u sarznom reaktoru pod visokim pritiskom brze je nego u istom tipu reaktora pod atmosferskim pritiskom. Optimalna temperatura za proces pod atmosferskim pritiskom je 30?C dok je u slucaju prisustva SC CO2 32?C. Primena cevnog reaktora sa keramickim membranama pod visokim pritiskom analizirana je koriscenjem model reakcije hidrolize CMC pod atmosferskim pritiskom i pod visokim pritiskom u prisustvu SC CO2. Reakcija je katalizovana povrsinom keramicke membrane na koju je kovalentnim vezama imobilisana lipaza izolovan? iz Humicola insolens. Hidroliza CMC u prisustvu SC CO2 i pod atmosferskim pritiskom pracena je u duzem vremenskom procesu pod stacionarnim uslovima. Veca produktivnost ostvarena je tokom reakcije realizovane u prisustvu SC CO2 nego kada je reakcija sprovedena pod atmosferskim pritiskom.