Metodologia de desativação acelerada em catalisadores com modelagem matemática do processo de HDT

Abstract

A challenge to the new regulatory requirements that restrict the sulfur emission is the suitable selection of hydrotreating catalysts (HDT). This work studies the accelerated deactivation by coke deposition in commercial HDT catalysts and the phenomenological modeling of the process. Deactivation by coke formation and deposition was studied using a kinetic approach with typical operating conditions of industrial units employing medium distillates. Continuous monitoring of the process through density, sulfur content and FTIR and NMR spectrometry analyzes allowed a simple and direct correlation between the composition of aromatic, sulfur and nitrogen compounds and catalytic bed activity. The phenomenological model, developed from a fixed bed reactor, allowed the kinetic parameters estimation with small deviations between experimental and predicted data by the model. The integration between the phenomenological model and experimental data of residual activity showed that the Accelerated Deactivation Methodology (MDA) is representative of the deactivation phenomenon in industrial units. Finaly, this model is a suitable and fast tool for the HDT catalysts evaluation.