The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 11, 1976
Filed:
Sep. 30, 1974
Susumu Fujiyama, Niigata, JA;
Minoru Takagawa, Niigata, JA;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JA;
Abstract
P-Tolualdehyde is separated with a high purify from a mixture of tolualdehyde isomers having a mole fraction of p-tolualdehyde of at least 0.27, on the basis of total tolualdehyde isomers by cooling the mixture to a crystallization temperature of -6.degree. to -60.degree.C, thereby crystallizing p-tolualdehyde, and separating the resulting p-tolualdehyde crystals from mother liquor. A solvent such as an aliphatic hydrocarbon having 1 to 9 carbon atoms or an alicyclic hydrocarbon having 3 to 9 carbon atoms can be added to the mixture before cooling to improve the crystallization conditions. The resulting crystals can be washed with a washing agent, such as said solvent, to remove the other isomers adhering to the crystals.