MALVERN Instruments has published a new application note which discusses the importance of particle size in heterogeneous catalyst materials, concluding that the company’s Mastersizer 3000 particle size analyser can be useful in achieving optimum reactivity.
The Mastersizer 3000 accurately determines particle size distribution for a wide range of catalyst materials, and also uses laser diffraction measurement to calculate specific surface area.
A further function, which Malvern says is unique, is to predict the attrition rate in a fluidized bed from dry powder measurements at different pressures.
A heterogeneous catalyst is present in one phase (solid) with the reactants in another (liquid or gas).
With such a catalyst, the reaction rate depends on the specific surface area of the solid material as this defines the available contact area between catalyst and reactants.
Decreasing the particle size in order to increase specific surface area is a well-understood and commonly applied strategy to improve reactivity. However, smaller particle sizes can be problematic, giving rise to health and safety issues from dust and potential loss of reactivity through unwanted agglomeration.
Malvern observes that there is usually an optimum particle size range for any given catalyst, which gives the best catalysis efficacy.
The Mastersizer 3000 laser diffraction particle size analyser provides rapid, accurate particle size distributions over a range from 0.01 to 3500um for both wet and dry dispersions with the minimum of effort, says the company.