Enabling cleaner fuels: desulfurization by adsorption to microporous coordination polymers.

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Organosulfur compounds like dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT) are key pollutants in diesel fuel.
• Current desulfurization methods struggle with refractory compounds and selectivity.
• Activated carbons exhibit poor selectivity for organosulfur removal from diesel.

Purpose of the Study:

• To evaluate the efficacy of Microporous Coordination Polymers (MCPs) as adsorbents for removing DBT and DMDBT from diesel fuel.
• To assess the adsorption capacity and selectivity of MCPs compared to conventional adsorbents.
• To investigate the regeneration capabilities of MCPs for sustainable fuel desulfurization.

Main Methods:

• Packed bed breakthrough experiments were conducted using UMCM-150, a specific MCP.
• Adsorption capacities for DBT and DMDBT were measured from both model and authentic diesel fuel.
• Selectivity was assessed by comparing adsorption of organosulfur compounds against other diesel components.
• Sorbent regeneration was performed using toluene at moderate temperatures.

Main Results:

• UMCM-150 demonstrated high adsorption capacities: 25.1 g S/kg for DBT and 24.3 g S/kg for DMDBT in authentic diesel.
• MCPs exhibited selective adsorption of organosulfur compounds, outperforming activated carbons.
• Complete regeneration of the MCP sorbent was achieved using toluene.
• Significant fuel desulfurization occurred before the breakthrough point.

Conclusions:

• MCPs are highly efficient and selective adsorbents for removing refractory organosulfur compounds from diesel fuel.
• The high capacity, selectivity, and regenerability of MCPs present a promising alternative to current desulfurization technologies.
• MCPs show significant potential for industrial application in clean fuel production.