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81 18.27 All these runs were made at the same are also told that the recycle rate is high enough to have mixed flow throughout. Thus changing the recycle rate from run 1 or from run 3 to 4 with no change in rate shows that film resistance does not infuence the rate. Next, if the particles were non-porous then the smaller size (runs should have double the rate of the larger size Cruns 3&4). This is not what is measured hence the results are not consistent with the guess of non-porous particles. Alright, let see if the results are consistent with the assumption of porous particles in the regime of no pore dffusion resistance the rates should be the same for large & small pellets -if in the regime of strong pore diffusion the rate should halve from 4 to 2 in going to the larger particles Our results are 1/2 way between these two extremes, hence we must be operating under conditions where pore diffusion is just beginning to influence the rate Thus we conclude: Porous particles, no film resistance, pore resistance just beginning to intrude & affect the rate