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Graphical abstract Highlights • A multi-functional gelator was developed from phenyllactic acid. • High efficient phenol removal was realized by gel material innovatively. • The powdered gel material achieved a rapid and efficient oil recovery. • Low cost and simple procedures lead the gel material to be feasible. • Multi-functional gel materials provide a novel avenue for water treatment. Abstract Supramolecular gels, a fascinating class of soft materials, are of great interest for their wide applications. In this work, a series of organic gelators derived from phenyllactic acid were prepared, and their gelation properties were further investigated. It was found that the gelator 1e bearing a hydrazine moiety could congeal 17 kinds of common organic liquids (polar and non-polar) efficiently. Meanwhile, the morphological structures and dominant factors of the gel were examined by scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), concentration and temperature-dependent 1H NMR. Crucially, the gelator displayed outstanding performances in toxic phenol removal and spilled oil and petroleum products recovery. Moreover, it also displayed a satisfactory recyclability, which will greatly promote its application in practice. These impressive results will provide a novel avenue for the water treatment and the development of functional supramolecular gel materials. [ABSTRACT FROM AUTHOR]

Abstract: Monoclinic BiVO4 single-crystallites with a polyhedral, spherical or porous octapod-like morphology were selectively prepared using the triblock copolymer P123 (HO(CH2CH2O)20(CH2CH(CH3)O)70(CH2CH2O)20H)-assisted hydrothermal method with bismuth nitrate and ammonium metavanadate as metal source and various bases as pH adjustor. The BiVO4 materials were well characterized and their photocatalytic activities were evaluated for the removal of methylene blue (MB) and phenol in the presence of a small amount of H2O2 under visible-light illumination. It is shown that the pH value of the precursor solution, surfactant, and hydrothermal temperature had an important impact on particle architecture of the BiVO4 product. The introduction of P123 favored the generation of BiVO4 with porous structures. The BiVO4 derived hydrothermally with P123 at pH 3 or 6 possessed good optical absorption performance both in UV- and visible-light regions and hence showed excellent photocatalytic activities for the degradation of MB and phenol. It is concluded that the high visible-light-driven catalytic performance of the porous octapod-like BiVO4 single-crystallites is associated with the higher surface area, porous structure, lower band gap energy, and unique particle morphology. Such porous BiVO4 materials are useful in the solar-light-driven photocatalytic treatment of organic-containing wastewater. [Copyright &y& Elsevier]

Abstract: In this study, three different approaches for the covalent immobilisation of the horseradish peroxidase (HRP) onto epoxy-activated acrylic polymers (Eupergit®C) were explored for the first time, direct HRP binding to the polymers via their oxirane groups, HRP binding to the polymers via a spacer made from adipic dihydrazide, and HRP binding to hydrazido polymer surfaces through the enzyme carbohydrate moiety previously modified by periodate oxidation. The periodate-mediated covalent immobilisation of the HRP on hydrazido Eupergit®C was found to be the most effective method for the preparation of biocatalysts. In this case, a maximum value of the immobilised enzyme activity of 127U/gsupport was found using an enzyme loading on the support of 35.2mg/gsupport. The free and the immobilised HRP were used to study the elimination of phenol in two batch reactors. As expected, the activity of the immobilised enzyme was lower than the activity of the free enzyme. Around 85% of enzyme activity is lost during the immobilisation. However, the reaction using immobilised enzyme showed that it was possible to reach high degrees of phenol removal (around 50%) using about one hundredth of the enzyme used in the soluble form. [Copyright &y& Elsevier]

Abstract: Photocatalytic degradation of phenol was investigated using the supported nano-TiO2/ZSM-5/silica gel (SNTZS) as a photocatalyst in a batch reactor. The prepared photocatalyst was characterized using XRD, TEM, FT-IR and BET surface area analysis. The synthesized photocatalyst composition was developed using nano-TiO2 as the photoactive component and zeolite (ZSM-5) as the adsorbents, all supported on silica gel using colloidal silica gel binder. The optimum formulation of SNTZS catalyst was observed to be (nano-TiO2:ZSM-5:silica gel:colloidal silica gel=1:0.6:0.6:1) which giving about 90% degradation of 50mg/L phenol solution in 180min. The SNTZS exhibited higher photocatalytic activity than that of the commercial Degussa P25 which only gave 67% degradation. Its high photocatalytic activity was due to its large specific surface area (275.7m2/g), small particle size (8.1nm), high crystalline quality of the synthesized catalyst and low electron–hole pairs recombination rate as ZSM-5 adsorbent was used. The SNTZS photocatalyst synthesized in this study also has been proven to have an excellent adhesion and reusability. [Copyright &y& Elsevier]

Abstract: Horseradish peroxidase was immobilized on the magnetic poly(glycidylmethacrylate-co-methylmethacrylate) (poly(GMA-MMA)), via covalent bonding and used for the treatment of phenolic wastewater in continuous systems. For this purposes, horseradish peroxidase (HRP) was covalently immobilized onto magnetic poly(GMA-MMA) beds using glutaraldehyde (GA) as a coupling agent. The maximum HRP immobilization capacity of the magnetic poly(GMA-MMA)-GA beads was 3.35mgg−1. The immobilized HRP retained 79% of the activity of the free HRP used for immobilization. The immobilized HRP was used for the removal of phenol and p-chlorophenol via polymerization of dissolved phenols in the presence of hydrogen peroxide (H2O2). The effect of pH and temperature on the phenol oxidation rate was investigated. The results were compared with the free HRP, which showed that the optimum pH value for the immobilized HRP is similar to that for the free HRP. The optimum pH value for free and immobilized HRP was observed at pH 7.0. The optimum temperature for phenols oxidation with immobilized HRP was between 25 and 35°C and the immobilized HRP has more resistance to temperature inactivation than that of the free form. Finally, the immobilized HRP was operated in a magnetically stabilized fluidized bed reactor, and phenols were successfully removed in the enzyme reactor. [Copyright &y& Elsevier]

Abstract: Phenol is a carcinogen to humans and is a serious health concern, even at low concentrations. The efficient removal of phenol inside waste water is highly desirable. Laser induced photo-catalysis has been applied for removal of phenol from waste water using p-type NiO semiconductor catalyst for the first time. The characteristics of phenol removal using laser induced photo-catalytic process were investigated. The dependence of phenol removal on laser energy (100–250mJ) and laser irradiation time (0–60min) was studied. The rate of phenol removal process was characterized using UV absorption spectrometry, Raman spectroscopy and gas chromatography. In addition, the role of pH changes during the removal process was also investigated. Laser induced photo-catalytic process is highly efficient in removal of phenol in water over a short period of time (in minutes) as compared to conventional methods using lamps (hours). The phenol removal process pursued the first order kinetics with decay constant=0.0125min−1. [Copyright &y& Elsevier]