Thermo-regulated water-organic biphasic system for phenol catalytic hydrogenation
Based on the fact that reactant phenol is immiscible with water at room temperature, while it is soluble at the reaction temperature, and the products cyclohexanone and cyclohexanol are slightly soluble in water, water as the green solvent instead of volatile solvents of organic compounds is proposed and used for phenol catalytic hydrogenation.For this process, the reaction rate is not limited by the solubility of reactant into water, and the products can be easily separated from the solvent water by phase separation technique after reaction.Meanwhile, the solvent water after reaction could be reused, which indicates that it is an environmental benign process.Furthermore, it might be a potential approach to increasing the reaction rate of organic hydrogenation and improving the selectivity to desired products due to the different adsorption-desorption properties of reactants and products on the surface of catalyst in various solvents.For example Raney Ni is of more powerful adsorption to H2 in water than in organic solvent.