Water-soluble poly:aromatic acids prepn. for prodn. of carbon@ adsorbents - by converting mesophase pitch into swellable prod. with complexing agent, followed by washing and treating with oxidising agent

摘要

In prodn. of low-impurity tar acids with a high COOH gp. content (I), by oxidn. of carbonaceous materials with a high aromatic hydrocarbon content (II); (II) is first converted into a swelling prod. (III) with a complexing agent (IV), then (IV) and the impurities are washed out with water, (III) is oxidised with an oxidising agent (V) until a water-soluble prod. is obtd., and the mixt. is worked up by evapn. of volatile components. Also claimed is a process for the prodn. of carbon adsorbents, by treatment of aromatic polycarboxylic acids (I) with activators (pref. H3PO4, ZnCl2, Fe chloride, or alkali or alkaline earth metal hydroxides), and heating at 300-900 deg.C. (II) is pitch, thermally treated pitch or mesophase pitch, (IV) is mainly H2SO4 or oleum contg. 0-60 wt.% free SO3, and pref. (V) is 5-30 wt.% aq. H2O2 soln. USE/ADVANTAGE - The process enables the prodn. of (I) contg. low levels of impurities and high COOH gp. content, which can be converted into carbon adsorbents by treatment with H3PO4 or ZnCl2 etc., followed by heating, avoiding the problems associated with previous methods (formation of alkali metals from thermal treatment with CO2.