A Nano-composite Catalyst

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A nano-composite catalyst: Pd nanoparticles deposited onto Cellulose nanocrystallites Overview: McGill University is seeking to out-license intellectual property relating to monodisperse Palladium nanoparticles (PdNPs) uniformly deposited onto colloidal cellulose nanocrystallites (CNCs). The resulting nano-composite material (3.6 + 0.8 nm) is a convenient active catalyst for hydrogenation reactions in water under mild reaction conditions: 4 bars of hydrogen/room temperature. The process is exemplified by the conversion of phenol to cyclohexanone as well as the model Heck reaction. Importantly these systems characterized as PdNPs@CNCs are colloidally stable in water, forming a homogeneous solution. They are easily separated from product using a simple dialysis system, thereby enabling the recovery of highly active catalyst for further applications in environmentally friendly chemical processes. Characteristics: Catalyst (weight) Phenol conversion (%) 3 h 24 h 0.5% PdNPs@CNCs (40 mg) 36 90 CNCs (40 mg) 0 0 Unsupported Pd (0.2 mg) 0 0 1% PdNPs@Al2O3 (20 mg) 44 100 5% PdNPs@Al2O3 (4 mg) 0 10 5% PdNPs@C (4 mg) 0 37 0.5% PdNPs@CNCs is an excellent catalyst for the conversion of phenol to cyclohexanone. Only 1%PdNPs@Al2O3 (20 mg) is comparable by yield. The catalytic activity of PdNPs@CNCs in the Heck coupling of styrene and iodobenzene as model substrates was evaluated in H2O-ACN, 1:1 at 100 C. Using K2CO3 as a base, 75% of iodobenzene was converted in stilbene within 24 h, at a molar ratio iodobenzene/Pd of 170/1.