INVESTIGATION OF DILUTE ACID HYDROLYSIS OF BLEACHED PULP TO MCC AND PULP FOR MFC

Microcrystalline cellulose (MCC) is a powder-like multifunctional product with wide-spread and diverse applications, especially in the food, pharmaceutical and cosmetic industries. This study investigates mild dilute acid hydrolysis of bleached hardwood pulp to MCC and to modified pulp for microfibrillated cellulose (MFC). The obtained temperature-time and concentration dependences show that for the production of MCC with degree of polymerization (DP) according to the European Pharmacopoeia, the temperature of the sulfuric acid hydrolysis process should be 130˚C and higher. Modified cellulose with a DP higher than 350 is obtained at a hydrolysis temperature of 120˚C and a sulfuric acid content of up to 2%. MFC obtained from acid hydrolysis modified cellulose was a stable, flowable and sprayable dispersion.