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In this work, we demonstrated the preparation of the carbonized montmorillonite/carboxymethyl cellulose (MMT/CMC) hybrids and their application as an adsorbent for efficient removal of 17β-Estradiol (βE2). X-ray diffractometer (XRD) results showed that CMC intercalation reached saturation at a CMC to MMT weight ratio of 1; transmission electron microscope (TEM) measurements clearly revealed that carbonization caused graphenes distribute on the MMT surfaces; pyrolysis temperature at 600 °C yielded novel MMT/CMC sample of high surface areas as reflected by Brunauer-Emmett-Teller (BET) surface area. The adsorbed amount of βE2 under various conditions decreased in the order MMT/CMC1:1(600) > MMT/CMC1:1(450) > MMT/CMC1:1(300) ∼ MMT/CMC2:1(600) ∼ MMT > MMT/CMC5:1(600). The removal of βE2 by MMT/CMC1:1(600) occurred very quickly, and the adsorption kinetics could be well fitted by the Ritchie nth-order kinetic model; the best-fit adsorption isotherm model was Freundlich model. The MMT/CMC1:1(600) also exhibited good regeneration performance after five adsorption/desorption cycles. The experimental results also showed that the adsorption of βE2 on the MMT/CMC1:1(600) composite could contribute to hydrophobic partitioning, π−π staking interaction, H-bond interaction, pore-filling effect and simple van der Waals interaction. This highly effective and novel adsorbent can be easily synthesized and regenerated, indicating its great potential in drinking and wastewater purification for endocrine disruptor compounds.

Allelochemicals are considered to be effective substances for controlling the outbreak of harmful cyanobacteria. In this study, Eleocharis dulcis peel fractions with an inhibitory effect on Microcystis aeruginosa were isolated by extraction and purification. The extracted organic compounds were identified by gas chromatography-mass spectrometry (GC-MS), and the allelopathic effect and mechanism underlying the inhibition of M. aeruginosawere explored. The results demonstrated that the exogenous compound, eriodictyol, corresponding to one of the detected flavonoids (C15H12O6) could inhibit the growth of M. aeruginosa, indicating that the flavonoid C15H12O6 is one of the allelochemicals contained in E. dulcis. Levels of chlorophyll a (Chl-a), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and reduced glutathione (GSH) of cell health in M. aeruginosa were analysed. Our results show that the damage to the antioxidant enzymes of algal cells caused by eriodictyol could be a main contributing factor to the decrease in the number of algal cells and even cell death.