Polymer-supported catalysts for clean preparation of n-butanol
Abstract
A new type of RANEY® metal catalyst supported by polymer was developed for the clean preparation of n-butanol. Unlike traditional supported catalysts, the newly developed alkalescent polyamide 6 (PA6) supported RANEY® nickel catalyst provided a 100.0% conversion of n-butyraldehyde without producing any detectable n-butyl ether, the main byproduct in industry. The significantly enhanced catalyst selectivity of the polymer-supported RANEY® metal catalyst was attributed to the elimination of the acid-catalyzed side reaction associated with RANEY® metals and traditional catalyst supports, such as Al2O3 and SiO2. By eliminating acid-catalyzed side reactions, therefore, green chemistry could be achieved through reducing resources and energy consumption in chemical reactions. Furthermore, the preparation and recycling of the polymer-supported catalysts are also much more eco-friendly than for traditional Al2O3-/SiO2-supported catalysts. The methodology developed in this study to use alkalescent polymers as the catalyst support could be applied to the whole catalyst family, including a series of important RANEY® metal catalysts (e.g., RANEY® nickel, RANEY® cobalt, RANEY® copper) used routinely in the chemical industry.