Influence of Flame Retardant on Manufacturing Carbon Fiber Absorbents

Abstract

A carbon fiber absorbent is prepared using a rayon-based fabric as a precursor, and a composite flame retardant of ammonium sulfate and dibasic ammonium phosphate as a pretreatment agent is used to prepare the carbon fiber absorbent in a continuous three- stage process in a high temperature environment of oxidation, carbonation, and activation. In the experiment, we investigate the effect of the flame retardant on the pore character istics of the carbon fiber absorbent and the removal of the flame retardant residues after treatment. The specific surface area, pore structure, and pore volume of the samples vary with the content of flame retardant, mostly due to increased flame retardant content. In addition, the experimental results show that almost all flame retardant residues can be removed in the chemical rinsing process. Also, most of the residues can be removed with ultrasonic treatment.

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