Letters to the editor

Single‐pellet cell for the measurement of intraparticle diffusion and convection

“…The analysis provided by Dogu et al (1989) for the diffusion-convection cell follows previous work by the authors for the diffusion cell; however, problems already recognized for the diffusion cell regarding boundary conditions and operating ranges have not been quantified (Rodrigues, 1991). Fott and Petrini (1982) used a related arrangement to measure permeability of porous catalysts.…”

Effect of Intraparticle Convection on the Effectiveness of a Biporous Pellet

“…An analysis of simultaneous convection (caused by an external pressure drop), diffusion, and reaction has earlier been considered in detail by the seminal papers by Komiyama and Inoue (1974) and Nir and Pismen (1977a,b). Since then a number of analyses dealing with intraparticle convection have been made (Cogan et al, 1982;Rodrigues et al, 1982;Cresswell, 1985;Dogu et al, 1989;Rodrigues, 1991;Rodrigues et al, 1991a,b;Lu et al, 1992a,b;Quinta Ferriera et al, 1992). Manufacture of large pore catalysts and adsorbents has made rapid progress to take advantage of the improved efficiency due to convection (Rodrigues et al, 1991a,b).…”