Valorization of Corn Stalk by the Production of Cellulose Nanofibers to Improve Recycled Paper Properties

Corn stalk, an agricultural waste, was valorized by the production of cellulose nanofibers (CNF), which were tested for improving recycled paper properties. CNF from eucalyptus kraft pulp (E-CNF) was used as a reference. Addition of 0.5% wt. CNF produced from corn organosolv pulp (C-CNF) to recycled paper increased the tensile index by 20%, whereas the same improvement with E-CNF was achieved at 1.5% wt. Tensile index was further enhanced by increasing the E-CNF, whereas C-CNF achieved its maximum effect at this dose. Different recycled furnish compositions were studied to evaluate C-CNF as a product additive. C-CNF improved tensile strength in all the different recycled furnishes studied. The tensile index improvement caused by C-CNF did not depend on the proportions of old newspaper and old magazine paper used. Addition of C-CNF to recycled corrugated board fluting increased the tensile strength, but to a slightly lower extent than in the case of recycled newsprint paper.