Efficient Organic Sulfur Adsorbent Controllable Synthesis And Performance Research

In recent years, as it is widely known that the organic sulfide in oil products has many detrimental effects, development of new deep desulfurization processes for oil products becomes one of the major challenges to the refining industry. Among the desulfurization methods, adsorption and oxidation desulfurization because of its mild operating condition, low investment cost and operation cost, good desulfurization effect and less environmental pollution become the focus of current research deep desulfurization.Adsorptive desulfurization(ADS) is an effective method for the selective capture of thiophenic sulfur compounds, and the ADS capacity of an adsorbent has been demonstrated to strongly depend on the dispersion degree of active species. Herein, series of zirconia-modified SBA-15(ZrSBA-15) framework with uniformly dispersed Cu sites have been prepared via a urea-assisted homogeneous deposition strategy, aiming for efficient adsorption towards thiophene. The resultant materials were thoroughly characterized by X-ray diffraction, N2 adsorptionedesorption isotherms, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and diffuse reflectance spectra analysis techniques. It was revealed that the Cu species were highly dispersed inside the ordered ZrSBA-15 framework with platelet morphology, rather than aggregation outside the surface, leading to excellent adsorption capacity for thiophene(up to 9.35 mg/g at 50 oC). The adsorption kinetics and isotherm data can be well described by the pseudo-second-order kinetics model and the Langmuir isotherm, respectively. Spent adsorbent can be regenerated by simple heating treatment in N2 at 500 oC, without obvious losing of thiophene adsorption capacity even after eight cycles.In addition, the dibenzothiophene(DBT) also explored oxidation desulfurization in this research. A layer-by-layer stabilization strategy was employed to immobilize active tungstophosphoric acid onto pentaethylenehexamine-preloaded acidic ZrSBA-15 with short pore channels. The composites were used as catalysts for the deep desulfurization of DBT with hydrogen peroxide as green oxidant. The main factors influencing the rate of removal of DBT were investigated in detail, including reaction temperature, the amount of catalyst and H2O2, and active species loading on. The catalyst exhibited excellent desulfurization activity under optimum testing conditions. Moreover, it could be recovered and reused for six reaction runs without a discernible decrease in its activity.