Electrochemical regeneration of phenol-saturated activated carbon – proposal of a reactor

Abstract

An electrochemical process was used to investigate the activated carbon regeneration efficiency (RE) saturated with aromatics. For this purpose, an electrochemical reactor was developed and the operational conditions of this equipment were investigated, which is applied in activated carbon regeneration process. The influence of regeneration parameters such as processing time, the current used, the polarity and the processing fluid (electrolyte) were studied. The performance of electrochemical regeneration was evaluated by adsorption tests, using phenol as adsorbate. The increase in current applied and the process time was found to enhance the RE. Another aspect that indicated a better reactor performance was the type of electrolyte used, showing best results for NaCl. The polarity showed the highest influence on the process, when the cathodic regeneration was more efficient. The electrochemical regeneration process developed in this study presented regeneration capacities greater than 100% when the best process conditions were used, showing that this form of regeneration for activated carbon saturated with aromatics is very promising.

Review on Coal-Based Activated Carbon: Preparation, Modification, Application, Regeneration, and Perspectives

“…and works on the principle of breaking the bonds between the adsorbent and adsorbate. Decomposition of AC works by breaking down adsorbates on the surface of the adsorbent and is classified into electrochemical, microbiological, chemical, and ultrasonic (which is also a desorption technique) methods. ,, …”

“…Decomposition of AC works by breaking down adsorbates on the surface of the adsorbent and is classified into electrochemical, microbiological, chemical, and ultrasonic (which is also a desorption technique) methods. 30,140,141 Ying et al 137 compared the effects of superheated steam regeneration and NaOH regeneration on phenol-saturated AC and carried out six-cycle adsorption/regeneration experiments under the best working conditions. The results showed that the regeneration efficiency of superheated steam decreased uniformly and steadily during each cycle of the adsorption/ regeneration experiment, while the regeneration efficiency of NaOH rapidly decreased after the first regeneration cycle and impurities gradually accumulated on the surface of regenerated AC with increasing cycle times.…”

“…The results showed that after 3 or 4 regeneration cycles, the radon adsorption efficiency was higher than that of the new AC. Zanella et al 141 developed an electrochemical reactor for regenerating saturated phenol AC. The results showed that when NaCl was used as the electrolyte, the regeneration efficiency was high.…”

Regeneration of dye-saturated activated carbon through advanced oxidative processes: A review

“…These problems have caused, in recent years, numerous efforts to be dedicated to the proposition of treatments for the regeneration of activated carbon that allow not only the removal of adsorbed contaminants, but also decompose the desorbed pollutants. Among the processes currently studied, advanced oxidative processes (AOPs) have received considerable attention [ 22 , 45 , 46 , 47 ]. AOPs are widely used in the treatment of wastewater containing a great diversity of contaminants due, mainly their efficiency in the removal of toxic and/or biorefractory pollutants and low cost [ 48 ].…”