Avaliação em unidade piloto da desativação de catalisadores industriais de hidrotratamento.

Abstract

The main objective of this work is to study the residual catalyst activity and the mechanisms of deactivation of catalyst from a lube-oil hydroprocessing industrial unit. In order to accomplish this, pilot plant tests were carried out followed by spent catalysts characterization. The residual catalytic activity was determined by HDA, HDS and HDN conversions and adjusted by a power law apparent kinetic model. Pilot plant tests revealed different levels of residual activity for spent catalyst samples. Catalyst samples taken from the first and last of the five catalytic beds showed higher deactivation than others. Catalyst characterization results pointed out two mechanisms as the main reason for the catalytic deactivation through the industrial reactor: poisoning by metal deposition (mainly Si and As) and coke deposition. Poisoning was the main deactivation mechanism for the first bed spent catalyst sample, while coke deposition was predominant at the last catalytic bed sample. Reactor temperature was identified as the most important operational parameter considering coke aging.