The influence of organic (acetic acid, citric acid and diethylene glycol) and inorganic (nitric acid and ammonia) plasticizing agents being used for alumina supports granulation on the properties of CoMoP/Al2O3 hydrotreating catalysts of gasoil fractions has been studied. Changing the textural characteristics of the supports by varying the plasticizing agent leads to different degrees of promotion of MoS2 particles by cobalt atoms, changes in the surface concentration of phosphorus, and changes in the morphology of the active component particles in the catalysts. Testing of the catalysts in the hydrotreating of model and real feedstocks has shown that the highest turnover frequency number of dibenzothiophene conversion on the active site of the catalyst is achieved with a catalyst based on a support plasticized with an ammonia solution. The lowest value is achieved with a catalyst based on a support prepared with diethylene glycol. In the series of samples CoMoP/Al-AcA → CoMoP/Al-NA → CoMoP/Al-CA → CoMoP/Al-DEG, a correlation has been observed between the surface concentration of P and Co content in CoMoS phase. The lower the surface concentration of P and the higher Co content in CoMoS phase, the higher the turn over frequency of dibenzothiophene. Testing results for the real feedstock showed good agreement with the textural characteristics of the catalysts.
Mukhacheva et al. (Wed,) studied this question.