Conversion of renewable biomethanol was studied from sugar beet pulp with pectin methyl esterases (PMEs). An analytical method for methanol and PME activity was developed based on potassium permanganate assay. Results showed that this method was sensitive, accurate and stable. Two PMEs, natural and mutated, were then produced and characterized. The kinetics parameters of Michaelis-Menten model and thermal deactivation model were determined. Based on the characterization results of PMEs, the methanol conversion from beet pulp was further studied and the effects of organisms, pH values, pulp size, and temperature were evaluated. After this, methods for separation and concentration of methanol from water, including striping, distillation and pervaporation, were studied and a model for the recovery of methanol from beet pulp after reaction was developed. Finally, the whole methanol conversion process was designed. The economic cost based on this design was estimated.