Solid Surfaces and the Solid-Gas Interface

Abstract

It is really heart-warming to see so many of my dear friends among you, and it is equally heart-warming to see so many unfamiliar faces, faces of those whom I have not had the privilege of meeting personally as yet. I never thought that the time would come when anyone would make a 20-minute address about me-let alone such an outstanding scientist and human being as Sir Hugh Taylor. I am profoundly grateful to him for honoring me with this wonderful address-it will always be one of the most treasured memories of my life-but I should like to assure him and assure you that I am keenly aware of my unworthiness of the honor bestowed upon me, and that I know full well that I am honored here because of his generosity and your generosity and not because of my own merits.For all that, I confess that in spite of the knowledge of my inadequacy I am very happy to receive the Kendall Company Award for 1961. So I should like to express my sincere thanks to the Kendall Company for establishing the award and donating the funds for it, to the American Chemical Society for administering the award, to my friends who nominated me for the award, and finally to the Award Committee, whose members are unknown to me, but who selected me for this great honor.I should like to say at this point also that practically all the contributions I have ever made were made in collaboration with others. So I have only partial share in all these contributions-and part of the honor I am now receiving should go to those with whom I collaborated. Nothing would please me more than to make my acknowledgment to each of them individually, but I am afraid this process would not be very interesting to most of you. I will mention, therefore, only four names now.The first is the name of my first boss, the first chemist who befriended me, the first man with whom I collaborated, and the first man who made me interested in surface chemistry-Paul Emmett. I owe more to Paul Emmett than I can say here, and I wish to acknowledge it with deep appreciation.Equal in importance in my scientific growth was Sir Hugh Taylor. Among other things, it was he who persuaded me to write the book, "The Adsorption of Gases and Vapors'," and as I wrote each chapter I sent it to him for his comments. Hugh was a source of guidance for me through much of my scientific life, and a source of inspiration through all of it. For that and for his friendship I want to express my deep gratitude.The two other names I have picked from the list of my coworkers, one from the first decade and one from the last. The first is Edward Teller, whose name is known to hundreds of millions, and the second is Lew Copeland, to whom I owe 5 Downloaded by UNIV OF CALIFORNIA SAN DIEGO on November 18, 2014 |

Powder Surface Area and Porosity

“…Brunauer [11] answers these criticisms by pointing out that lateral interaction between adsorbate molecules necessarily increases as the surface becomes more completely covered. The interaction with the surface, however, decreases with increasing adsorption up to monolayer coverage since on an energetically heterogeneous surface the high energy sites will be occupied at lower relative pressures with occupancy of the lower energy sites occurring nearer to completion of the monolayer.…”

“…It is this value of S which is summed in column 14. The summation is multiplied by M from the following decrement to calculate the film volume decrease in column 11.…”

Review of Shale Gas Sorption and Its Models

“…On the basis of the kinetic theory, both the Langmuir model and the BET model assume energetically homogeneous surfaces; that is, all adsorption sites have the same adsorption potential. 52 The first adsorbed layer always covers the entire surface before the formulation of the second and/or higher adsorbed layers (Figure 3). As a naturally occurred geomaterial, surfaces of organic shale consist of imperfect surfaces with heteroatoms, resulting in a variation in adsorption potential at various localities of surfaces.…”

“…On the basis of the kinetic theory, both the Langmuir model and the BET model assume energetically homogeneous surfaces; that is, all adsorption sites have the same adsorption potential . The first adsorbed layer always covers the entire surface before the formulation of the second and/or higher adsorbed layers (Figure ).…”

Equilibrium-Based Modeling of Chemical Sorption on Soils and Soil Constituents

“…(1967) state that statistical and thermodynamic derivations (rather than Langmuir's kinetic derivation) consider this assumption valid only for energetically uniform surfaces with no lateral interaction. Lateral interactions and surface heterogeneity exert opposing effects on the heat of adsorption; thus, these compensating factors may maintain the heat of adsorption approximately constant for an adsorption isotherm to obey the Langmuir equation (Brunauer, 1961;Brunauer et aI., 1967;Hiemenz, 1977).…”