Choice of Binder in Catalyst Preparation
Catalysts are employed in various industrial applications such as water purification, food, medical, cosmetology, automotive, gas purification, petroleum and precious metal recovery. Catalyst have the ability of speeding up the overall reaction without undergoing any permanent chemical change, as such, most catalyst are expected to be inert. All catalyst consist of an active phase, a support and a promoter or an inhibiter. When it comes to solid catalysts, one more component is key in obtaining the final catalyst; a binder!
The key role of the binder is to obtain a pelletized form of the final catalyst powder. This ensures the availability of catalysts with strong mechanical integrity for various applications. Binders used in catalyst preparation include silica, alumina, and aluminum phosphate solution. However, literature shows that the type of binder can interfere with the final products to either form new products or absorb some of the products. The pelletizing of a catalyst may or may not include a binder, depending on the particle size of the catalyst powder. Where a binder is necessary, there is a need to consider its effect on the final activity of the catalyst and its overall contribution in the reaction process.
There is therefore the need to have a wholistic look at the catalyst preparation process, that is from the selection of active metals, support, preparation technique, through to the production of the final catalyst pellets to access the possibility of any side reactions that may interfere with the final results.