Fig. 4: Criterion for maximizing the effectiveness factor.
From: Assessment of transport phenomena in catalyst effectiveness for chemical polyolefin recycling
a, Variation in the product distribution with stirring rates for HDPE200 and PP340 with the impeller stirrer. b,c, Two-phase CFD simulations of the hydrogen fraction in the mid z–x plane for different stirrer types (b) and different stirring rates for the impeller stirrer (c). d, Correlation between the effectiveness factor, defined as the ratio between the yield of C1–C45 and maximum yield of C1–C45 in a, and the modified power number for HDPE200 and PP340, calculated using the stirring rates in a and the simulated fraction of H2 in Extended Data Fig. 5. Reaction and simulation conditions: T = 498 K, \({p}_{{{\rm{H}}}_{2}}\) = 20 bar and catalyst/plastic ratio = 0.05.
