Catalysis

Adsorption

Moisture

Engineering

Materials science

Molecular sieve

Coating

Flue-gas desulfurization

Inorganic chemistry

Chemical engineering

Organic chemistry

Thiophene

Oxygen

Zeolite

Sulfur

Chemistry

Polydimethylsiloxane

Copper

Nature Communications

The zeolite Cu(I)Y is promising for adsorptive removal of thiophenic sulfur compounds from transportation fuels. However, its application is seriously hindered by the instability of Cu(I), which is easily oxidized to Cu(II) even under atmospheric environment due to the coexistence of moisture and oxygen. Here, we report the adjustment of zeolite microenvironment from hydrophilic to superhydrophobic status by coating polydimethylsiloxane (yielding Cu(I)Y@P), which isolates moisture entering the pores and subsequently stabilizes Cu(I) despite the presence of oxygen. Cu(I) in Cu(I)Y@P is stable upon exposure to humid atmosphere for 6 months, while almost all Cu(I) is oxidized to Cu(II) in Cu(I)Y for only 2 weeks. The optimized Cu(I)Y@P material after moisture exposure can remove 532 μmol g-1 of thiophene and is much superior to Cu(I)Y (116 μmol g-1), regardless of similar uptakes for unexposed adsorbents. Remarkably, Cu(I)Y@P shows excellent adsorption capacity of desulfurization for water-containing model fuel.

Enhancing oxidation resistance of Cu(I) by tailoring microenvironment in zeolites for efficient adsorptive desulfurization