A bifunctional cobalt catalyst for the synthesis of waxy diesel fuel by the Fischer–Tropsch method – from the development to implementation. Part 3. The experience of industrial implementation of the preparation technology

Abstract

The work summarizes the results of testing the technology for preparing a bifunctional cobalt catalyst for the synthesis of hydrocarbons from CO and H2, obtained by extruding a mixture of Co-Al2O3 /SiO2 catalyst powders and HZSM-5 zeolite with a binder – boehmite in industrial conditions (2 batches of 50 kg each were prepared). The catalyst technology was implemented on the equipment of Ishimbay Specialized Chemical Catalyst Plant LLC. The obtained industrial samples of the catalyst were characterized by XRF, TPR H2, DTG, and tested in the synthesis of hydrocarbons from CO and H2 at a temperature of 250 °C, a pressure of 2.0 MPa, GHSV 1000 h–1. It has been shown that the implementation of the technology of a bifunctional cobalt catalyst for the production of low pour point diesel fuel in industrial conditions makes it possible to reproduce the characteristics of the catalyst obtained in laboratory conditions. The technology for producing the catalyst can be recommended for the production of industrial batches. It was determined that changes in the heat treatment conditions of the catalyst, as well as the presence/absence of a peptizer and pore former do not lead to a significant decrease in the productivity of C5+ hydrocarbons. The contentof the diesel fraction in C5+ products obtained from industrial samples of the catalyst remains at the level of the value obtained from the laboratory sample of the catalyst. At the same time, the low-temperature properties of diesel fuel obtained using all catalyst samples have similar values. Using an industrial sample synthesized without the use of a peptizing agent and a pore-forming component, the best lowtemperature properties of diesel fuel were achieved – the cloud point and fluid loss point were minus 16 and minus 24, respectively.