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The significance of using date palm surface fiber as a biosorbent to remove pollutants from wastewater is evaluated. This material, which has advantages over other natural adsorbing materials, for being inexpensive, renewable, eco‐friendly, and available in large scale worldwide, has been widely used for the removal of several types of pollutants such as acid and basic dyes, heavy metals, pesticides, oils, and organic compounds. In addition to its use as an effective biosorbent to remove pollutants from wastewater, date palm surface fiber exhibits wide future perspectives in several other applications. [ABSTRACT FROM AUTHOR]

The removal of trivalent chromium [Cr(III)] from tannery wastewater is necessary for health regulation compliance. In this work, two precipitating agents, namely, sodium hydroxide (NaOH) and calcium hydroxide [Ca(OH)2] were used to remove Cr(III) from Amatong Tannery wastewater by chemical precipitation. Wastewater characterization along with the most affecting parameters such as the effect of pH on Cr(III)) removal and sludge volume, average sludge volume and the settling time were investigated. The results show that optimum pH for Cr(III) removal by NaOH and Ca(OH)2 were found as 8.5 and 8.5-9.0, respectively, with supernatant Cr(III) concentration as 1.23 and 4.1 mg/L, respectively; the removal efficiency of NaOH was 99.94% and 99.8% for Ca(OH)2. At optimum pH, NaOH exhibited much sludge volume, whereas Ca(OH)2 displayed higher supernatant volume. NaOH: Ca(OH)2 volume ratio for sludge volume at optimum pH and average sludge volume were 1:1.24 and 1:1.8, respectively. [ABSTRACT FROM AUTHOR]

Microreactor technology is increasingly applied in the chemical‐pharmaceutical industry for safer and more efficient drug production as compared to the traditional batch process. This technology is employed for the first time to study the production of 2‐[methyl(pyridin‐2‐yl)amino]ethanol, the first intermediate in rosiglitazone synthesis. Under the optimum operating conditions, a single microreactor chip at 160 °C allowed to produce the equivalent of more than five batch reactors at 120 °C. The kinetic study indicated that the reaction is second order. Thermodynamic parameters were determined by the Eyring equation and density functional theory (DFT) calculations with good agreement. DFT results suggested a concerted nucleophilic aromatic substitution reaction mechanism. [ABSTRACT FROM AUTHOR]

One of the difficulties related to oil exploration is transporting heavy oil since its high viscosity causes high‐pressure drop and energy consumption. In order to save energy, the core annular flow (CAF) can be applied where a two‐phase annular flow occurs, with peripheral water flowing offering a reduction in energy expenditure. The multiphase flow was studied experimentally in a simple purpose‐built unit. To theoretically handle the CAF, computational fluid dynamics simulations were done with the commercial package Ansys Fluent. The flow was considered turbulent, isothermal, incompressible, and 3D, and both stationary and transient cases were evaluated. The volume‐of‐fluid model was adopted for the multiphase system, and water/oil interface and turbulence phenomena were well predicted. [ABSTRACT FROM AUTHOR]

This study focused on kinetics and equilibrium isotherms of mercury biosorption from water using dry biomass of Chlorella vulgaris as biosorbent at pH 5.0. Biosorption tests were performed at 2.0 g/L biomass dosage varying initial Hg concentration from 11.0 to 90.6 mg/L. The Lagergren equation was found to best describe the process, with R2 of 0.984 and specific rate constant of 0.029 ± 0.004 min−1. Although equilibrium data were well fitted by the Dubinin and Radushkevich isotherm (R2 = 0.870; qDR = 16.6 mg/g), important insights on phenomenological events occurring at equilibrium were concurrently provided by the Lamgmuir one (R2 = 0.826; q0 = 32.6 mg/g; KL = 0.059 L/mg). FT-IR analysis confirmed that Hg biosorption took place via physisorption. Since C. vulgaris is a fresh-water microalga that can be easily cultivated anywhere, these promising results suggest its possible use as an effective, low-cost biosorbent to treat industrial effluents contaminated by this metal. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the production of bacteriocin-like inhibitory substances ( BLIS) by Bifidobacterium animalis subsp. lactis in whey supplemented with yeast extract, inulin, Tween-80 or l-cysteine. Cell growth, acidification, glucose and lactose consumption as well as BLIS production were measured during fermentations carried out in shake flasks. The best additive for both cell growth and BLIS production was shown to be yeast extract, which gave the highest concentrations of biomass (9.9 log cfu/mL) and BLIS (800 AU/mL). In a bench-scale fermentor, B. lactis growth and BLIS production were between 6% and 25% higher than in flasks depending on the conditions assayed. [ABSTRACT FROM AUTHOR]

Chitosan and keratin were tested as low cost biosorbents to remove phenol from water solutions at variable temperature (20- 50°C), initial phenol concentration (10-90 mg L-1) and pH (5.0-10.0), and fixed biosorbent dosage (10 g L-1). The pseudo-second order kinetic model exhibited the best fit to the experimental data and allowed estimating theoretical values of sorption capacity of 4.51 mg g-1 with keratin and 2.87 mg g-1 with chitosan. Equilibrium isotherms, described at best by the Freundlich model, pointed out that keratin (KF = 1.34 mg1-1/n L1/n g-1) was more effective than chitosan (KF = 0.19 mg1-1/n L1/n g-1) in phenol removal, although the sorption intensity was almost coincident (n = 1.18-1.19). The results of tests performed at different temperatures suggested a novel thermodynamic approach based on the occurrence of a sorbent inactivation equilibrium, whose changes of enthalpy and entropy were estimated to be 35.7 kJ mol-1 and 118 J mol-1 K-1 with chitosan, and 256 kJ mol-1 and 845 J mol-1 K-1 with keratin. The main functional groups involved in phenol sorption by both raw and phenol-bound materials were identified by FT-IR spectroscopy. [ABSTRACT FROM AUTHOR]