GB1152927A - Improved Coke Binder Pitch - Google Patents

Abstract

1,152,927. Coke binder pitch. ESSO RESEARCH & ENG. CO. 15 Sept., 1967, No. 42103/67. Heading C5E. Pitch binder for electrodes is made from petroleum tar fractions or coal tar fractions by dealkylating the feedstock in a fluidized coke bed at 1300‹ to 1600‹ F under a pressure of 0 to 100 p.s.i.g. for 0À1 to 10 seconds, recovering the dealkylated vapour and converting it at temperatures of 650‹ to 800‹ F. for 1 to 6 hours to a condensed aromatic fraction, and fractionating the converted material to recover the aromatic fraction as bottoms. In a modification of the above method, an intermediate distillate (B.R. 400‹ to 825‹ F.) is recovered from the fractionating step and oxidized at 200‹ to 650‹ F. for 1 to 24 hours to produce a pitch. The final product in both cases boils above 800‹ F., has a Conradson carbon number of at least 50 and a softening point in the range 180‹ to 290‹ F. In an illustrated embodiment, the dealkylated vapour, after solids removal, is quenched to 700‹ to 900‹ F. by injecting an oil, e.g. a midrange boiling fraction from the fractionator, into the vapour, and conversion is carried out in a condenser-soaker where C 4 and lighter gases are flashed off. Feed-stocks which may be utilized include heavy virgin residuals; the bottoms from the distillation of catalytically cracked gas oils, the bottoms from steam cracking light or heavy cycle oils at 1200‹ to 1500‹ F., coal tar pitch, coal tar oils of B.R. 500‹ to 850‹ F. and shale oil boiling above 650‹ F. A preferred feed-stock is produced by catalytically cracking a mid-boiling petroleum fraction and steam cracking the product at 1200‹ to 1500‹ F., and. recovering the tar bottoms.. Comparative examples are described.