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:
Sep. 14, 1982
Filed:
Jul. 28, 1981
Stephen E Belsky, Parsippany, NJ (US);
Chempolil T Mathew, Randolph, NJ (US);
Allied Corporation, Morris Township, Morris County, NJ (US);
Abstract
Methylnaphthalenes, indole and other tar bases are recovered from a base-extracted coal tar distillation fraction. In one form, an aqueous salt solution of pH 0.5-3 extracts other tar bases from the starting material, and thereafter both products are recovered from the raffinate by several alternate methods including ethylene glycol extraction and extractive distillation. In other forms, the starting material is extracted with ethylene glycol and the extract is distilled to recover several products including indole. The raffinate of ethylene glycol extraction contains methylnaphthalenes and other hydrocarbons and can be purified to solvent-grade material.