Scale-up of a fixed bed electrochemical reactor consisting of parallel screen electrode used for p-aminophenol production

• Published in: Electrochimica acta 2007-12, Vol.53 (4), p.1671-1679
• Main Authors: Abbar, Ali H., Sulaymon, Abbas H., Jalhoom, Moayyed G.
• Format: Article
• Language: English
• Subjects: Chemistry; Effectiveness factor; Electrochemical reduction; Electrochemistry; Exact sciences and technology; Fixed bed electrode; General and physical chemistry; Kinetics and mechanism of reactions; Nitrobenzene; p-Aminophenol
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2007.07.075

The behavior of a fixed bed consisting of amalgamated copper screens has been investigated for the electrolytic reduction of nitrobenzene to p-aminophenol under potentiostatic condition (controlled potential). The preparative electrolysis of nitrobenzene was carried out using supporting electrolytes consisting of 2 M H 2SO 4 in a solution of 50% 2-propanol/50% water (v/v). The criterion for scale-up ( ɛ n ) was determined through application of one-dimensional model. The polarization curves that describe the reduction of nitrobenzene to p-aminophenol were obtained experimentally by using a pilot scale for different nitrobenzene concentrations and flow rates of catholyte. It was found that the effectiveness factor ( ɛ n ) increases with increasing flow rate, and decreasing nitrobenzene concentration. An optimum thickness of bed equal to 0.6 cm was obtained, in which the effectiveness factor not less than 0.588, to ensure a well distribution of current and potential.