Innovative technologies to remove alkylphenols from wastewater: a review

Alkylphenols and alkylphenol polyethoxylates are emerging hazardous contaminants due in particular to their endocrine-disrupting properties. These compounds originate from consumer products such as paints and latex paints, adhesives, inks, formulation of pesticides, paper industry, textile and leather industry, petroleum recovery chemicals, metal working fluids, personal care products, washing agents, cleaners, and detergents. Since classical wastewater treatments have not been designed to remove alkylphenols, these compounds end up polluting ecosystems. Here we review three advanced methods to remove alkylphenols and derivatives. First, innovative polymers, such as cyclodextrin polymers and molecularly imprinted polymers, allow to remove alkylphenols from effluents by adsorption. Second, biotechnologies such as microalgae, biodegradation in constructed wetlands and sequential anaerobic–aerobic digestion treatments. Third, advanced oxidation processes to degrade recalcitrant alkylphenols, e.g., ozone-carbon coupling, electrochemical degradation, photocatalysis, zero-valent iron-activated persulfate coupling, and catalytic ozonation.