Catalytic Refining Lignin-Derived Monomers: Seesaw Effect between Nanoparticle and Single-Atom Pt
Weiyan Wang1, Shangjian Li1, Qian Qiang2,3
1School of Chemical Engineering, Xiangtan University, Xiangtan, Hunan, 411105, P.R. China.
Angewandte Chemie (International Ed. in English)
|May 21, 2024
Summary
Single-atom catalysts (SACs) like Pt/TiO2-H efficiently upgrade lignin monomers via selective demethoxylation. This method offers a sustainable route to valuable chemicals, surpassing traditional nanoparticle catalysts.
Area of Science:
- Catalysis
- Materials Science
- Renewable Energy
Background:
- Lignin valorization is crucial for sustainable chemical production.
- Selective upgrading of lignin-derived monomers remains challenging.
- Atomically dispersed catalysts offer unique reactivity.
Purpose of the Study:
- To develop a single-atom catalyst (SAC) for selective demethoxylation of lignin-derived compounds.
- To investigate the catalytic performance and mechanism of Pt/TiO2-H.
- To demonstrate the generality of the synthesis strategy for various SACs.
Main Methods:
- In situ interfacial redox reaction for Pt adsorption on TiO2 oxygen vacancies.
- Synthesis of single-atom Pt/TiO2-H catalyst.
- Catalytic testing for upgrading 4-propylguaiacol under specific conditions (3 MPa H2, 250°C, 3h).
- Comparison with nanoparticle catalysts.
Main Results:
- Pt/TiO2-H achieved 96.9% conversion and 93.3% demethoxylation selectivity.
- SAC suppressed benzene ring hydrogenation and deep deoxygenation compared to nanoparticles.
- Weak hydrogen spillover capacity and reduced CAr-OCH3 bond cleavage energy barrier were key factors.
- The method successfully produced other SACs (Au, Pd, Ir, Ru) on TiO2-H.
- SAC Pt/TiO2-H showed versatility and stability in demethoxylating various lignin monomers.
Conclusions:
- Atomically dispersed Pt on TiO2-H is superior for selective demethoxylation of lignin derivatives.
- This approach provides a renewable alternative to fossil-based chemicals.
- The facile synthesis strategy enables a library of SACs for diverse applications.
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