Evaluation of Fenton and modified Fenton oxidation coupled with membrane distillation for produced water treatment: Benefits, challenges, and effluent toxicity

Membrane distillation is a promising technology to desalinate hypersaline produced waters. However, the organic content can foul and wet membrane, while some fractions may pass into distillate impair its quality. In this study, applicability of traditional Fenton process was investigated preliminarily optimized as pre-treatment synthetic water for following step membrane distillation. The also compared modified system, whereby safe iron ligands, i.e., ethylenediamine-N,N′-disuccinate citrate, were used overcome practical limitations reaction. oxidation pre-treatments achieved up 55% removal dissolved carbon almost complete degradation low molecular weight toxic contaminants. steps did not improve productivity process, but they allowed obtaining final effluent with significantly higher quality in terms reduced Vibrio fischeri inhibition, half maximal effective concentration (EC 50 ) values 25 times those measured raw water. addition ligands during simplified resulted an slightly lower toxicity use Fenton. • Thermal degraded target contaminants oxidative decreased organics effluent. Coupled Traditional provided best toxicity. Modified nearly all solutions.