ExxonMobil

About: ExxonMobil is a company organization based out in Irving, Texas, United States. It is known for research contribution in the topics: Catalysis & Polymer. The organization has 16969 authors who have published 23758 publications receiving 535713 citations. The organization is also known as: Exxon Mobil Corporation & Exxon Mobil Corp..

Toward Separation and Purification of Olefins Using Dithiolene Complexes: An Electrochemical Approach

Abstract: The complex Ni[S2C2(CF3)2]2reacts with light olefins, including ethylene and propylene, selectively and reversibly. The reaction is not poisoned by hydrogen gas, carbon monoxide, acetylene, or hydrogen sulfide, which are commonly present in olefin streams, presumably because olefin binding occurs through the sulfur ligand rather than the metal center. The reversible reaction of olefins with Ni[S2C2(CN)2]2 n ( n = 0, −1, −2) can be controlled electrochemically, where the oxidation state–dependent binding and release of olefins are fast on the electrochemical time scale. The observed tolerance to poisons and controllable electrochemical reactivity present an alternative approach to the separation of olefins from complex streams.

A New Look at Predicting Gas-Well Load-Up

Abstract: This paper discusses results of field tests conducted to verify minimum flow rate (critical rate) required to keep low-pressure gas wells unloaded and compares results to previous work. This paper also covers liquid yield effects, liquid sources, verification that wellhead conditions control onset of load-up, and effects of temperature, gas/liquid gravities, wellbore diameter, and packer/tubing setting depth.

Granular flow: Friction and the dilatancy transition.

Abstract: Molecular-dynamics simulations of noncohesive granular assemblies under shear are described. At low shear rate \ensuremath{\gamma}\ifmmode \dot{}\else \.{}\fi{}, the assembly is unstable to uniform motion and exhibits stick-slip dynamics involving periodic dilatancy transitions and gravitational compactification. Steady-state motion occurs at larger \ensuremath{\gamma}\ifmmode \dot{}\else \.{}\fi{} where 6--12 layers of grains flow over a compact, static assembly. A phase boundary, characterized by a discontinuity in \ensuremath{\gamma}\ifmmode \dot{}\else \.{}\fi{} and an enhanced normal stress, separates the static and flowing regions. In the steady-state regime, dilatancy leads to a shear stress that is independent of \ensuremath{\gamma}\ifmmode \dot{}\else \.{}\fi{}.