Investigation on the adsorption desulfurization effect of carboxyl and phosphotungstic acid modified UiO-66

UiO-66 loading carboxyl and phosphotungstic acid has a good affinity to thiophene (TH). The synthesized catalyst, changed its original structure, which can increase its reactive site and enhance the interaction with thiophene (TH) in order to improve the adsorption performance. Then the structural changes were analyzed by XRD, FT-IR, SEM, BET, EDS and other characterization methods. Through static experiments of adsorption desulfurization, it is found that when the adsorption time is 240 min, the adsorption temperature is 30 degrees C and the oil-to-agent ratio is 100:1, the adsorption effect: UiO-66-(COOH)(2) (UC2) > UiO-66, the highest adsorption capacity can reach 89.99 mg/g; while PTA@UiO-66 (PAU) can reach adsorption equilibrium at 210 min, it has better desulfurization performance than UiO-66. After being recycled for 5 times, the adsorption effect is only slightly decreased: the adsorption capacity of UC2 was still 78.02% of the initial adsorption capacity, while that of PAU was 76.07% of the initial adsorption capacity. According to the adsorption kinetics, the adsorption process of thiophene on the adsorbent UC2 is more consistent with W-M model, and the adsorption of PAU is more in line with the pseudo-first order kinetic equation. In addition, it also includes the process of intraparticle diffusion and liquid film diffusion.

Automated summary

UiO-66 loaded with carboxyl and phosphotungstic acid demonstrates a strong affinity for thiophene, showing improved adsorption performance and reactive site interaction. Structural changes were analyzed using various characterization methods, and it was found that PAU outperformed UiO-66 in terms of desulfurization performance, adsorption capacity, and recyclability.