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Polydopamine/polyethyleneimine-decorated membranes were fabricated with excellent surface hydrophilicity and high water permeability for oil/water emulsion separation under atmospheric pressure.

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Activated carbon derived from finger citron residue (FAC) was tested as a new type of adsorbents to remove the harmful dyes (anionic dye methyl orange (MO) and cationic dye methylene blue (MB)) from contaminated water. Liquid phase adsorption experiments were conducted and the maximum adsorptive capacity was determined. Various conditions were evaluated, including initial dye concentration, adsorbent dosage, contact time, solution pH, and temperature. The Langmuir and Freundlich adsorption models were used to describe the equilibrium isotherm and isotherm constant calculation. It was found that the adsorption capacity of FAC is much higher than those of the other types of activated carbons. Maximum equilibrium adsorption capacities of 934.58 mg/g and 581.40 mg/g for MO and MB were achieved.Three simplified kinetic models including pseudo-first-order, pseudo-second-order and intra-particle diffusion equations were used to investigate the adsorption process.The pseudo-second-order equation was followed for adsorption of MO and MB on FAC. Temperature-dependent adsorption behaviors of MO and MB show that the adsorption is a spontaneous and endothermic process accompanying an entropy increases (the driving force of the adsorption). This work indicates that FAC could be employed as a low cost alternative to commercially available activated carbon in the removal of dyes from wastewater.

A comparative evaluation of different cell disruption methods for the release of lipids from marine Chlorella vulgaris cells was investigated. The cell growth of C. vulgaris was observed. Lipid concentrations from different disruption methods were determined, and the fatty acid composition of the extracted lipids was analyzed. The results showed that average productivity of C. vulgaris biomass was 208 mg L⁻¹ day⁻¹. The lipid concentrations of C. vulgaris were 5%, 6%, 29%, 15%, 10%, 7%, 22%, 24%, and 18% when using grinding with quartz sand under wet condition, grinding with quartz sand under dehydrated condition, grinding in liquid nitrogen, ultrasonication, bead milling, enzymatic lysis by snailase, enzymatic lysis by lysozyme, enzymatic lysis by cellulose, and microwaves, respectively. The shortest disruption time was 2 min by grinding in liquid nitrogen. The unsaturated and saturated fatty acid contents of C. vulgaris were 71.76% and 28.24%, respectively. The extracted lipids displayed a suitable fatty acid profile for biodiesel [C16:0 (~23%), C16:1 (~23%), and C18:1 (~45%)]. Overall, grinding in liquid nitrogen was identified as the most effective method in terms of disruption efficiency and time.

NaY zeolite catalysts with and without potassium salt modifications were studied with respect to dehydration of lactic acid to acrylic acid. The selectivity for acrylic acid could be dramatically enhanced by modification of the NaY catalysts with potassium salts. The KI-modified NaY catalyst exhibited the best catalytic performance for lactic acid dehydration, over which 97.6% conversion and 67.9% acrylic acid selectivity could be gained at 598 K. Characterizations with TGA, XRD, N2 adsorption, 27Al MAS NMR, XPS, NH3-TPD, CO2-TPD, and mechanism analysis revealed that the counteranions in potassium salts exerted a significant influence on the catalytic behaviors via an electronic effect.

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Silica-decorated polypropylene microfiltration membranes were fabricated via a facile biomimetic silicification process on the polydopamine/polyethylenimine-modified surfaces. The membranes exhibit superhydrophilicity and underwater superoleophobicity derived from the inherent hydrophilicity and the well-defined micronanocomposite structures of the silica-decorated surfaces. They can be applied in varieties of oil-in-water emulsions separation with high permeate flux (above 1200 L/m(2)h under 0.04 MPa) and oil rejection (above 99%). The membranes also have relatively high oil breakthrough pressure reaching 0.16 MPa due to the microporous structure, showing great potential for practical applications. Furthermore, such mussel-inspired intermediate layer provides us a convenient and powerful tool to fabricate organic-inorganic hybrid membranes for advanced applications.