A multiscale three-zone reactive mixing model for engineering a scale separation in enzymatic hydrolysis of cellulose.

This multiscale three-zone reactive mixing model provides a theoretical framework for engineering a scale separation in batch enzymatic hydrolysis of cellulose to strategize significant leaps in glucose yields. Formulated using the Liapunov-Schmidt method of the classical bifurcation theory, our model explores the multiscale spatiotemporal dynamics between the fundamental processes of macromixing (convection) and micromixing (diffusion) of the enzymes (Endoglucanase, Exoglucanase, β-glucasidase) and reducing sugars, adsorption and desorption of enzymes on the solid cellulosic substrates, and the product-inhibited liquid and solid phase enzymatic reactions that depolymerize microcrystalline cellulose (Avicel). The model is validated for a range of substrate loadings (2-5%) using our experimental results for the two asymptotic cases of no mixing and continuous mixing, as well as for the macro/micro scale-separated optimal mixing strategy that increases the glucose yield by up to 26% by macromixing completely for an initial period followed by micromixing for the remaining duration of the hydrolysis.