Calorimetric study of the esterification of cellulose by H3PO4-HNO3 mixtures

1. The esterification of cellulose is achieved with greatest efficiency relative to reaction time and nitrogen content in the products in a mixture containing 80% HNO3, 15% H3PO4, and 5% H2O. 2. The esterification of cellulose in this mixture proceeds under milder conditions and with a lower heat effect than upon using 100% HNO3 or HNO3-H2SO4, mixtures.