Improving the quality of pure crude-benzole-rectification products

Journal Article · Sat Jan 01 04:00:00 EST 1977 · Coke Chem., USSR (Engl. Transl.); (United States)

OSTI ID:5809263

Mikhno, S I; Nekrasov, A Ya; Kulyasova, S V; Sheryshova, N G

In connection with the expansion of the chemical industry, which has entailed the introduction of complex new processes and the introduction of more stringent requirements for the quality of final and intermediate-products, more severe requirements have been imposed on the quality of the pure products yielded by rectification of crude benzole; this has been reflected in changes in State Standards. The principal purity indices of the products in question include: (1) distillation limits; (2) purity with respect to unsaturated compounds (color in the sulfuric acid reaction and bromine number); (3) carbon bisulfide content, %; (4) thiopene content, %; (5) crystallization temperature, /sup 0/C. All the quality indices of the synthesis-grade benzene and toluene produced by the plant have exhibited a continuous rise from year to year and at present are in complete conformity with the requirements of the new State Standards; the quality indices of the synthesis-grade benzene are better than those stipulated in the proposed new State Standard. Various measures have been implemented to achieve these indices. In preparing for the manufacture of synthesis-grade benzene, the flowscheme used in the rectification department was redesigned in accordance with the recommendations of Giprokoks; a number of new units permitting employment of a continuous process were installed (an intermediate column was introduced between the benzene and toluene columns and a still-type column was installed to provide semicontinuous production of xylene derivatives. Installation of an intermediate column not only makes the process continuous but also promotes production of high-quality benzene and toluene. These improvements became possible after better rectification-column operating regimes were worked out.

• OSTI ID: 5809263
• Journal Information: Coke Chem., USSR (Engl. Transl.); (United States), Journal Name: Coke Chem., USSR (Engl. Transl.); (United States) Vol. 7; ISSN COKCA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010500* -- Coal
Lignite
& Peat-- Products & By-Products
AROMATICS
BENZENE
EUROPE
HYDROCARBONS
ORGANIC COMPOUNDS
PURIFICATION
TOLUENE
USSR
XYLENES