Production of Carbon Black in Turbulent Spray Flames of Coal Tar Distillates

Abstract

Conventional carbon black production occurs by pyrolysis after heavy aromatic feedstock is injected into the post-combustor region of furnace black reactors. The current work examines the conversion of the coal tar distillate in turbulent spray flames to demonstrate a more compact reactor configuration. Coal tar distillates diluted in toluene is atomized and burned in a standardized flame spray synthesis configuration, known as SpraySyn. Flame conditions are characterized by thermocouple, soot pyrometry and image analysis and product particle properties are examined by TEM and Raman spectroscopy. The measured flame temperature corresponds to the range of temperatures used in the furnace black process, but the current synthesis includes oxidizing conditions and faster residence times. The resulting carbon black particles are aggregates with primary particle sizes on the small end of the carbon black size spectrum, according to analysis of TEM images. Carbon black, formed under a range of flame temperatures, show Raman spectra with features resembling typical carbon black materials. Conversion of coal tar distillate to carbon black by direct flame synthesis may be a scalable method to produce high-surface area grades without a conventional pyrolysis reactor stage.