| 摘要 |
<p>Furnace carbon black is made by thermal decomposition of a fluid hydrocarbon feedstock in a process wherein the quality of at least one property of the carbon black, for example the modulus in rubber, is adjusted by introducing a substance comprising an alkali metal into the furnace, the adjustment being effected by introducing an amount of the alkali metal substance sufficient to effect only a part of the quality adjustment and maintaining the carbon black in the reaction zone of the furnace for a period of time longer than that necessary to produce a tar-free carbon black and sufficient to complete quality adjustment. The alkali metal may be potassium, for example as potassium chloride, and may be used in an amount of from 1 to 200 parts by weight of potassium per million parts by weight of feedstock. Other compounds referred to are sulphates, nitrates, carbonates, bromides, iodides, acetates, naphthenates, oleates, lanolates and metal alkyls. The carbon black may be maintained in the reaction zone for a period of time which is 1.5 to 9 times the period of time necessary to produce a tar-free carbon black. Reference has been directed by the Comptroller to Specification 886,523.</p> |
