May the Knudsen equation be legitimately, or at least usefully, applied to dilute adsorbable gas flow in mesoporous media?

► Large literature gap in Ruthven-Bhatia debate on adsorbable-gas quasiKnudsen flow. ► Missing relevant earlier data show reduced-permeability minimum vs. T or adsorbability. ► Missing successful earlier model interpretations of the above data are reviewed. ► Replotting of above earlier data proves their conformity to quasiKnudsen flow. ► Replotted recent quasiKnudsen data exhibit the above reduced-permeability minimum.