| 主权项 |
1. Process for the production of pitch, comprising the following steps at atmospheric pressure:
a) preheating of a feedstock up to a initial reaction temperature; b) continuous and uniform heating, in conditions of a first reflux at an initial reaction temperature of between 300° C. and 370° C., for a time sufficient to promote reactions between hydrocarbon components, in a homogeneous liquid phase, generating: gaseous products that are eliminated and residual products in the reaction conditions; c) distillation of the residual products generated in stage b) up to a maximum temperature between 380° C. and 450° C., generating: residual products, gaseous products that are eliminated, and volatile products that are removed by condensation in the proportion between 5% and 60% by weight in relation to the feedstock; d) continuous and uniform heating of the residual products generated in the preceding distillation stage in reflux conditions at a temperature between 5° C. and 50° C. below the maximum temperature of the distillation, for a time between 1 and 60 times less than that of the heating in stage b), to promote reactions, generating: gaseous products that are removed and residual products in the reaction conditions; e) distillation of the residual products generated in stage d) up to a maximum temperature between 390° C. and 485° C., generating: gaseous products that are eliminated, volatile products that are removed by condensation, and residual products; f) sequential repetition of the two preceding stages, d) and e), to obtain residual products comprising pitch with a yield in relation to the feedstock between 30% and 60% by weight; and g) recovery of the pitch under refrigeration to specify a predominantly isotropic end product; wherein steps a)-g) occur at atmospheric pressure. |
