Patents by Inventor Stephen Robota

Stephen Robota has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4436942
    Abstract: A process for the preparation of compounds of the formula ##STR1## which comprises contacting compounds of the formula ##STR2## wherein n is 0 to 5, andm is 1 to 3in the vapor phase, with hydrogen fluoride in the presence of a granular, porous high surface area catalyst prepared by treating .alpha.-alumina with hydrogen fluoride.
    Type: Grant
    Filed: April 30, 1979
    Date of Patent: March 13, 1984
    Assignee: Occidental Chemical Corporation
    Inventors: Charles G. Rader, Stephen Robota
  • Patent number: 4317805
    Abstract: A method of removing hydrogen fluoride from gaseous mixtures of hydrogen fluoride and hydrogen chloride, which contain up to about 5 percent by weight of hydrogen fluoride, is described. The method comprises initially contacting the gaseous mixture with a particulate, substantially anhydrous, bed of alkaline earth metal chloride material, for example, calcium chloride, to produce an effluent gas mixture having a substantially reduced hydrogen fluoride content. The effluent gas is then contacted with a secondary treatment bed of particulate, substantially anhydrous, alkaline earth metal chloride material, for example, calcium chloride, to produce a product gas containing less than 20 ppm of hydrogen fluoride. The temperature of the secondary treatment bed is maintained in the range from about -20.degree. to about +20.degree. C., and, more preferably, in the range from about 0.degree. to about 5.degree. C.
    Type: Grant
    Filed: June 16, 1980
    Date of Patent: March 2, 1982
    Assignee: Hooker Chemicals & Plastics Corp.
    Inventors: Stephen Robota, Yusuf A. Baxamusa
  • Patent number: 4299606
    Abstract: A process is disclosed for recovering HF and HCl in substantially purified form from a gaseous mixture containing HF, HCl and halogenated organic vapors. The process comprises:A. feeding the gaseous mixture to the lower part of a rectification column to provide an upward flow of gases therein, the column having a temperature in the upper part of from about -40.degree. C. to about -85.degree. C., and having a temperature in its lower part in the range of from about -30.degree. C. to about 19.degree. C., the column also having a countercurrent flow of a liquid and a gas,B. withdrawing liquid HF from the bottom of the rectification column,C. withdrawing a gas from the top of the rectification column, and feeding the thus withdrawn gas to a condenser,D. condensing at least a portion of the withdrawn gas of step C to a liquid,E. feeding a portion of the condensed liquid of step D to the upper part of the rectification column, andF. recovering HCl gas from the condenser.
    Type: Grant
    Filed: January 3, 1978
    Date of Patent: November 10, 1981
    Assignee: Hooker Chemicals & Plastics Corp.
    Inventors: Stephen Robota, Alastair J. H. McGregor, Gregory A. R. Trollope
  • Patent number: 4250122
    Abstract: A process for the para-directed chlorination of alkylbenzenes comprises reacting an alkylbenzene with chlorine in the presence of a catalyst mixture previously prepared by the steps of (a) reacting sulfur monochloride with toluene or chlorotoluene in the presence of a Lewis acid catalyst, and (b) reacting the reaction product of step (a) with chlorine.
    Type: Grant
    Filed: September 7, 1979
    Date of Patent: February 10, 1981
    Assignee: Hooker Chemicals & Plastics Corp.
    Inventors: Henry C. Lin, Stephen Robota
  • Patent number: 4183873
    Abstract: A process for the preparation of compounds of the formula:R.sub.n Ar(CF.sub.w' X.sub.p').sub.Zcomprises contacting compounds of the formula:R.sub.n Ar(CF.sub.w X.sub.p).sub.Zin the liquid phase, with hydrogen fluoride in the presence of molybdenum chloride whereinAr is arylR is a substituent on the aryl nucleus selected from the group consisting of aryl, substituted aryl, halogen, alkyl, alkoxy, substituted alkyl, and substituted alkoxy;n is 0 to 9;X is halogen atom other than fluorine;w is 0 to 2;p is 1 to 3;w' is 1 to 3, and is greater than w;p' is 0 to 2, and is less than p;w+p is 3;w'+p' is 3;Z is 1-10; andthe maximum value of n+Z is 10.
    Type: Grant
    Filed: June 5, 1978
    Date of Patent: January 15, 1980
    Assignee: Hooker Chemicals & Plastics Corp.
    Inventors: Yusuf A. Baxamusa, Stephen Robota
  • Patent number: 4098832
    Abstract: A process for the preparation of compounds of the formulaR.sub.n Ar(CF.sub.2w.spsb.' X.sub.p.spsb.').sub.Zcomprises contacting compounds of the formulaR.sub.n Ar(CF.sub.w X.sub.p).sub.Zin the liquid phase, with hydrogen fluoride in the presense of molybdenum chloride whereinAr is arylR is a substituent on the aryl nucleus selected from the group consisting of aryl, substituted aryl, halogen, alkyl, alkoxy, and substituted alkyl;n is 0 to 9;X is halogen atom other than fluorine;W is 0 to 2;p is 1 to 3;w' is 1 to 3, and is greater than w;p' is 0 to 2, and is less than p;W + p is 3;w' + p' is 3;Z is 1-10; andThe maximum value of n + Z is 10.
    Type: Grant
    Filed: November 1, 1976
    Date of Patent: July 4, 1978
    Assignee: Hooker Chemicals & Plastics Corp.
    Inventors: Yusuf A. Baxamusa, Stephen Robota
  • Patent number: 4077850
    Abstract: A method for the purification of monochlorobenzene contaminated with partly chlorinated aliphatic compounds comprises (a) selectively photochlorinating the contaminated monochlorobenzene to convert the partly chlorinated aliphatic compounds to substantially fully chlorinated aliphatic compounds and (b) separating the monochlorobenzene from the more fully chlorinated aliphatic compounds by distillation.
    Type: Grant
    Filed: August 30, 1976
    Date of Patent: March 7, 1978
    Assignee: Hooker Chemicals & Plastics Corporation
    Inventors: Stephen Robota, James A. Whelan