超滤和反应器偶联组合进行干酪素酶解反应

在研究底物浓度对干酪素酶解反应影响的基础上 ,提出干酪素酶解反应应当以边分离边反应的形式进行。因此以三种不同的操作方法 (反应与膜分离分别进行 ;连续偶联反应 ;半连续反应和连续偶联反应组合 ) ,对超滤和反应器的偶联组合进行了研究。其中以半间歇与连续偶联反应器的偶联组合为最佳。当底物浓度为 10 0 g· L-1时 ,得率达到 97% ,比反应与分离分别进行的方式提高了 16 .7%。在此三种方法中 ,超滤对总氮的截留率分别为 σ1=0 .11+0 .0 81t;σ2 =0 .15 +0 .0 0 7t;σ3 =0 .2 1- 8.8× 10 -6t。反应与超滤同时进行时透过液的稳定膜通量为 3.5 L·h-1· m-2

STUDY ON APPLICATION OF THE COMBINATION OF ULTRAFILTRATERS AND REACTORS TO CASEIN ZYMOHYDROLUSIS

The effect of casein concentration on the yield was previously studied. The results showed that a coupling of reaction and separation for casein zymohydrolusis is preferred. Thus, the Combination of a ultrafiltrater and a membrane reactor for casein zymohydrolysis was studied in three procedres (zymohydrolysis and membrane separation were carried out separately; membrane reactor system was continuously operated; semibatch reactor and continuous reactor with ultrafiltrater were combined). The maximal yield reached to 97%. The trapped ratios for total nitrogen can be written as σ1＝0.11+0.081 t;σ2＝0.15+0.007 t;σ3＝0.21－8.8×10－6 t individually. The concentration polarization phenomena were severe when the reaction and membrane separation were carried out separately. Different types of the membranes seldom effect on the ultrafiltrate flux since thick gel layer was formed on the membrane at low pH. The flux was decreased sharply during the filtrating procedure. The stable flux for the two types of reactor systems with ultrafiltrate membrane was 3.5L·h－1·m－2．