Removal of tyrosol from water by adsorption on carbonaceous materials and electrochemical advanced oxidation processes

Abstract

This work compares the ability of physical and chemical treatments, namely adsorption and electrochemical advanced oxidation processes, to remove tyrosol from aqueous medium. Adsorption on graphene nanoplatelets (GNPs) performed much better than that with a graphite intercalation compound. Adsorption isotherms were found to follow the Freundlich model (R = 0.96), which is characteristic of a chemisorption process. Successful electrochemical regeneration enables 5 successive adsorption/regeneration cycles before corrosion of GNPs occurs. Other typical aromatic contaminants that may coexist with tyrosol can be also adsorbed on GNPs. Percentage of regeneration efficiency of GNPs showed a higher affinity towards Lewis acids group compounds and a lower one towards Lewis base. The treatment of 100 mL of 0.723 mM tyrosol solutions in non-chlorinated and chlorinated matrices at pH 3.0 was carried out by electrochemical oxidation with electrogenerated HO (EO-HO), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF). Trials were made with a BDD anode and an air-diffusion cathode at 10-30 mA cm. Hydroxyl radicals formed at the anode from water oxidation and/or in the bulk from Fenton's reaction between added Fe and generated HO, along with active chlorine produced in chlorinated medium, were the main oxidants. Tyrosol concentration always decayed following a pseudo-first-order kinetics and its mineralization rose as EO-HO < EF < PEF, more rapidly in the chlorinated matrix. The potent photolysis of intermediates under UVA radiation explained the almost total mineralization achieved by PEF in the latter medium. The effect of current density and tyrosol content on the performance of all processes was examined.

Effect of Fe2+ and Fe0 Applied Photo‐Fenton Processes on Sludge Disintegration

“…3, for raw sludge, the germination percentage was 70 %, which means that sprout germination was inhibited. This may be due to harmful organic compounds or microorganisms in sludge 41. With the CFP/UV‐C process, the germination percentage increased up to 100 % which proves that toxicity decreases better and deteriorates significantly after disintegration of the sludge.…”

Combined adsorption and electrochemical oxidation of perfluorooctanoic acid (PFOA) using graphite intercalated compound

“…At lower concentration, equilibrium was reached within an hour. These equilibrium times are relatively longer than for PFOS and other organics which typically require less than 20 min of adsorption on GIC (Brown et al 2004 ; Hussain et al 2015 ; Flores et al 2018 ; Trzcinski and Harada 2023 ). This is relatively faster that previous adsorption studies on porous activated carbon and anion-exchange resins which can take more than 50 h to reach equilibrium (Du et al 2014 ).…”

A Review on Electrochemical Degradation and Biopolymer Adsorption Treatments for Toxic Compounds in Pharmaceutical Effluents

“…They include the combination of electrochemical reduction-oxidation (ERÀ O), electro-Fenton (EF), and irradiated EO, as well as the application of biochemical methods [73]. In electrochemical reduction-oxidation, generally, oxidants produced on the anode surface can degrade most organic matter [8,87]. However, the complete mineralisation of HOCs is usually not removed [88].…”