The conversion of waste paper fibers into sugars by hydrolysis of their cellulosic content can provide a cheap and high grade feedstock for various small and large molecule products. The hydrolysis process with enzymes is difficult though on account of the presence of mineral inhibitors in recycled pulps and also the lower accessibility of cellulose due to fiber hornification effects. Effective adjuvants such as surfactants can reduce inhibitory effects. The enzymatic hydrolysis process can be very effectively enhanced by integrating proper separation steps with the reactor and thereby effectively recycle the reactants.
The present contribution describes an effective integrated membrane bioreactor for this application and a mathematical model based on hydrolysis kinetics. The operation of the separation is optimized with the model and predictions are confirmed experimentally.