Patents by Inventor Dane Chang

Dane Chang 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: 5098681
    Abstract: Sulfur dioxide is removed from a fluid containing SO.sub.2 by employing as an absorbent therefor an aqueous solution of compounds represented by Formulas I and II: ##STR1## wherein each R.sup.1 or R.sup.2 is independently hydrogen; an alkyl group; a hydroxyalkyl group; an aldehyde group; a carboxylic acid or salt group; an alkyl group containing at least one carboxylic ester, carboxylic acid or salt, ether, aldehyde, ketone or sulfoxide; and wherein at least one R.sup.1 or R.sup.2 is a carbonyl-containing group, such as an aldehyde group, a carboxylic acid containing group, a carboxyl ester group, or a ketone-containing group; ##STR2## wherein each R.sup.3 is independently hydrogen; an alkyl group; a hydroxyalkyl group; an aldehyde group; a carboxylic acid or salt group; or an alkyl, aryl, or aralkyl group containing at least one carboxylic ester, a carboxylic acid or salt, ether, aldehyde, ketones or sulfoxide group. The absorbent solution preferably can be thermally regenerated by heating to remove SO.sub.
    Type: Grant
    Filed: August 16, 1990
    Date of Patent: March 24, 1992
    Assignee: The Dow Chemical Company
    Inventors: Steven H. Christiansen, Dane Chang, Druce K. Crump
  • Patent number: 4980471
    Abstract: The 2-piperazinones are made by reacting a 1-cyano-1-hydroxyalkane with ethylenediamine or a substituted ethylenediamine in aqueous solution. The process to make the 2-piperazinones suitable as a regenerable sulfur dioxide absorbing medium requires that the cyano compound be present in at least a molar equivalent amount to the diamine and that the resulting 2-piperazinone product be sparged with an inert gas.
    Type: Grant
    Filed: October 6, 1989
    Date of Patent: December 25, 1990
    Assignee: The Dow Chemical Company
    Inventors: Steven H. Christiansen, David A. Wilson, Dane Chang
  • Patent number: 4895600
    Abstract: Asphalt compositions are improved by incorporating therein the reaction produce of (a) a phosphorus-containing compound, (b) an amine or polyamine and (c) a carbonyl-containing compound as an anti-stripping agent. These asphalt compositions are useful as a pavement material by blending with an aggregate.
    Type: Grant
    Filed: July 28, 1988
    Date of Patent: January 23, 1990
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, Druce K. Crump
  • Patent number: 4839404
    Abstract: A composition useful as a pavement material comprising a mixture of asphalt, aggregate and an interpolymer of an .alpha.-olefin monomer selected from the group consisting of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid or an ionomer of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid.
    Type: Grant
    Filed: July 28, 1986
    Date of Patent: June 13, 1989
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, David L. Wolfe
  • Patent number: 4786329
    Abstract: Asphalt compositions are improved by incorporating therein the reaction product of (a) a phosphorus-containing compound, (b) an amine or polyamine and (c) a carbonyl-containing compound as an anti-stripping agent. These asphalt compositions are useful as a pavement material by blending with an aggregate.
    Type: Grant
    Filed: September 9, 1987
    Date of Patent: November 22, 1988
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, Druce K. Crump
  • Patent number: 4765969
    Abstract: A continuous process for removing hydrogen sulfide from a gas stream by contacting the gas stream with a solution of ammonium hydroxide to produce an effluent liquid stream comprising ammonium sulfide which is fed to a heating zone maintained at least at the boiling temperature of said solution and supplied with an oxygen containing gas sparge wherein ammonia and hydrogen sulfide are removed from said zone as vapor and sulfur is removed from said zone as an aqueous dispersion, the sulfur being separated in a filtration zone from the residual aqueous liquid which is recycled back to a contact zone together with said ammonia and said hydrogen sulfide vapor.
    Type: Grant
    Filed: January 15, 1987
    Date of Patent: August 23, 1988
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, Michael C. McGaugh
  • Patent number: 4765839
    Abstract: Bituminous compositions are improved by incorporating therein the reaction product of an organic amine with a substituted nitrogen-containing heterocyclic compound as an anti-stripping agent. These compositions are useful as a pavement material by blending with an aggregate.
    Type: Grant
    Filed: November 19, 1987
    Date of Patent: August 23, 1988
    Assignee: The Dow Chemical Company
    Inventors: Duane S. Treybig, Dane Chang
  • Patent number: 4765873
    Abstract: A process for removing hydrogen sulfide from a gaseous stream containing hydrogen sulfide by contacting said stream with an aqueous solution of ammonium hydroxide to produce ammonium sulfide; converting said ammonium sulfide to an ammonium polysulfide intermediate in an electrolytic cell at ambient temperature and pressure; and oxidizing said ammonium polysulfide to sulfur in a heating zone utilizing an oxygen containing gas sparge.
    Type: Grant
    Filed: December 6, 1985
    Date of Patent: August 23, 1988
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, Michael C. McGaugh
  • Patent number: 4724003
    Abstract: Asphalt compositions are improved by incorporating therein the reaction product of a hydrocarbyl substituted nitrogen-containing aromatic heterocyclic compound such as 2,4,6-trimethylpyridine, an aldehyde such as formaldehyde or ketone such as acetone and an amine such as a mixture of C.sub.10 -C.sub.18 aliphatic monoamides.
    Type: Grant
    Filed: February 24, 1987
    Date of Patent: February 9, 1988
    Assignee: The Dow Chemical Company
    Inventors: Duane S. Treybig, Dane Chang
  • Patent number: 4701484
    Abstract: Asphalt compositions are improved by incorporating therein the reaction product of an amine or polyamine with an aldehyde as an anti-stripping agent. These compositions are useful as a pavement material by blending with an aggregate.
    Type: Grant
    Filed: February 24, 1987
    Date of Patent: October 20, 1987
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, Duane S. Treybig
  • Patent number: 4643886
    Abstract: A method for removing hydrogen sulfide from a gaseous stream by contacting the gaseous stream with a polyvalent metal chelate present in an aqueous alkaline scrubbing solution including the regeneration of the polyvalent metal chelate in an electrolytic cell and automatic control of the pH of said aqueous alkaline scrubbing solution at about 7 to 9.
    Type: Grant
    Filed: December 6, 1985
    Date of Patent: February 17, 1987
    Assignee: The Dow Chemical Company
    Inventors: Dane Chang, Stephen A. Bedell