Abstract: The hydrolysis of carbonyl sulfide is substantially improved by utilizing titanium dioxide particles as a catalyst. It is especially favorable, if the titanium dioxide particle are sintered and treated with sodium hydroxide or sodium aluminate. Through such a treatment, the catalyst can be regenerated and reutilized.
Abstract: A process for heat treating spent pot linings from Hall-Heroult electrolytic cells which comprise carbon and silico-aluminous materials impregnated with fluorides. The pot linings are ground to a particle size less than 5 mm, and formed into an intimate mixture with calcium sulfate or calcium sulfate dihydrate having a particle size less than 1 mm. The mixture is injected into the center of a vortex formed by a flow of circulating hot gas at the top part of a reactor at a temperature between 700.degree. and 1100.degree. C., and extracted from the bottom part of the reaction at a temperature between 400.degree. and 750.degree. C. after a contact time of less than 2 seconds.
Type:
Grant
Filed:
June 25, 1993
Date of Patent:
November 15, 1994
Assignee:
Aluminium Pechiney
Inventors:
Eric Barrillon, Pierre Personnet, Jean-Claude Bontron
Abstract: A macroreticulate polymer is provided for removing water vapor and oxidants from a gas having the formula: ##STR1## wherein Ar is a heteroaromatic moiety, M is bonded to the heteroaromatic moiety and is selected from the group consisting of lithium, sodium, potassium, alkyl magnesium, alkyl zinc, and dialkylaluminum, R is an organic moiety and R.sub.1 is a polymerized moiety forming the molecular backbone of said polymer.
Abstract: A process is disclosed for reversibly absorbing acid gases from gaseous mixtures wherein a salt hydrate is heated to a temperature above its melting point and exposed to an acid gas which is absorbed by the salt hydrate to form a salt hydrate melt. This melt is thereafter cooled to a temperature sufficient to solidify the melt and to desorb the acid gas from the solidified salt hydrate. Preferred salt hydrates include tetramethylammonium fluoride tetrahydrate and tetraethylammonium acetate tetrahydrate.
Type:
Grant
Filed:
November 10, 1992
Date of Patent:
August 16, 1994
Assignee:
Air Products and Chemicals, Inc.
Inventors:
Robert Quinn, Guido P. Pez, John B. Appleby
Abstract: The process of the present invention provides for the sorption of residual gas in a vessel by means of a non-activated, non-evaporated barium getter. It comprises the steps of reducing an alloy of Ba.sub.z +(Ba.sub.1-x A.sub.x).sub.n B.sub.m to a particle size of less than 5 mm, under vacuum or an inert gas atmosphere and then placing the particulate alloy in the vessel. Upon exposing the particulate alloy to the residual gas in the vessel at room temperature the gas is sorbed. The metal A is a metal selected from the group consisting of elements of Group IIa of the periodic table of elements, excluding barium. The metal B is selected from the group consisting of elements of Group Ib, IIb, IIIa, IVa and Va of the periodic table of elements. Furthermore n=1, 2, 3 or 4 and m=1, 2 or 5, whereas o.ltoreq..times..ltoreq.0.5 and z is a value from zero to such a value that the total barium in the alloy is less than 95% by weight of the alloy.
Abstract: The process of the present invention provides for the sorption of unwanted gas in a vessel by means of a non-evaporated barium getter. It comprises the steps of reducing an alloy of Ba.sub.1-x A.sub.x Li.sub.4-y B.sub.y to a particle size of less than 5 mm, under vacuum or an inert gas atmosphere and then placing the reduced alloy in the vessel. Upon exposing the reduced alloy to the residual gas in the vessel at a temperature of less than 150.degree. C., the gas is sorbed. The metal A is a metal chosen from the group consisting of elements of Group IIa of the periodic table of elements, excluding barium. The metal B is chosen from the group consisting of elements of Group IIIa of the periodic table of elements. Preferably 0.ltoreq.x.ltoreq.0.5 and 0.ltoreq.y.ltoreq.3.5.