(104e) Novel Nanohybrid Catalysts Capable of Stabilizing Oil/Water Emulsions and Catalyzing Reactions at the Interface

A novel system has been developed to catalyze reactions at the oil/water interface of a biphasic liquid system. This was accomplished through the use of nanohybrids composed of hydrophilic SiO₂ particles and hydrophobic single-wall carbon nanotubes (SWNTs) particles generated through the CoMoCAT process. These nanohybrids are inherently amphiphilic, and tend to populate the interface in a biphasic water/oil liquid system. Upon the addition of kinetic energy, these particles stabilize pickering emulsions. Preferential orientation of the particles was characterized by XPS and TEM. Catalytically active metals were deposited on the nanohybrids, resulting in reactions at the oil/water interface. Proof-of-concept runs were conducted by depositing Pd on the nanohybrids and creating an emulsion in a mixture of decalin and water. Octanal was introduced to the oil phase and glutaraldehyde the water phase as reactive model molecules. Hydrogenation reactions were conducted at 100°C and 200psig. Results verify a modification of selectivity and activity through reaction at the interface when compared with the single phases alone. Etherification and phase transfer were also observed under these conditions. This provides proof-of-concept for a very promising catalytic system with many potential applications for the upgrading and separation of products in the liquid phase. Potential applications include bio-oil upgrading, as well as various specialty chemical and pharmaceutical applications where selective reaction and separation based on water solubility are desirable.