Recuperação de solvente (acetonitrila) por métodos de destilação

Abstract

The Technology School of the State University of Amazonas (EST-UEA) currently has nine chemical laboratories in operation. Ten years ago, there were no chemical laboratories in the Unit. The amount of waste generated by these laboratories tends to grow, and there is no imple-mentation of recovery methods. Acetonitrile used in High Performance Liquid Chromatography equipment is a product that has risen in price in recent years and is harmful to health. The objec-tive of the work was to survey the residues generated by EST-UEA chemical laboratories and to recover acetonitrile through distillation using existing techniques and equipment on campus. The survey waste was made through interviews with the responsible for the laboratories. Acetonitrile was treated by simple distillation, followed by freezing to separate the acetonitrile-water azeotrope and fractional distillation, with fraction separation according to the boiling point of the substance. Samples were analyzed by Gas Chromatography-Mass Spectrometry and acetonitrile at 94.75% purity was obtained in one of the fractions. It was concluded that the EST-UEA has adequate control of the chemical residues generated by the laboratories and that the recovery of acetonitrile presented a lower cost than the acquisition of the new product, but the method re-quires adjustments to increase the degree of purity of the substance.