Ultra-deep catalytic adsorptive desulfurization of diesel fuel using
Ti-silica gel adsorbent at low Ti-loading
Abstract
In this work, the effective ultra-deep catalytic adsorptive
desulfurization (CADS) using Ti-silica gel adsorbent at low Ti loading
range (< 1%) was investigated. The superior CADS capacity
(37.3 mg-S/g-A) and high TOF value (432 h-1) for dibenzothiophene (DBT)
were achieved at 0.6% of Ti loading with high dispersion and low Ti
coordination. The catalytic oxidation of DBT conformed to the
pseudo-first-order kinetic model, and the corresponding rate equation
was well described as , where the TiOOR is determined as the
intermediate to enable the DBT oxidation to the corresponding sulfone
(DBTO2). The effectiveness of CADS using Ti-SG was verified in various
real low-sulfur diesels with varied sulfur concentrations and O/S ratios
in the dynamic fixed-bed adsorption and multi-cycle regenerations. This
work provides insights on using low-cost bifunctional catalytic
adsorbents at low Ti loading for effective CADS to realize ultra-deep
desulfurization of transportation fuels.