Erythromycin degradation by an esterase in enzymatic membrane reactors

1 Introduction Pharmaceuticals products (PPs) and endocrine disrupting chemicals (EDCs) as well as their transformation products have been detected in almost all effluents from sewage facilities, in surface water, in groundwater, adsorbed on sediments and even in drinking water [1,2]. Ecotoxicity studies have demonstrated that pharmaceutical pollutants could affect the growth, reproduction and behavior of birds, fishes, invertebrates, plants and bacteria [3,4]. Some recently published studies report that the presence of low concentrations of antibiotics in the wastewaters may develop antibiotic resistance in the whole environment [5, 6]. As previously reported by Demarche et al. [7], the use of enzymes might be beneficial to enhance or complement conventional wastewater treatments. As far as enzymes are relatively expensive the reuse of the biocatalyst appears to be essential to ensure the economic and industrial viability of the process. Enzymatic membrane reactors appear to be an interesting alternative since they enable to couple reaction and separation [8]. In fact, in such enzymatic reactors, the substrate is continuously brought in contact with the biocatalyst, which is retained by the membrane, either freely circulating with the retentate or fixed on or within the membrane and the reaction products are recovered in the permeate. This work describes the study of erythromycin degradation by an EreB esterase in free and immobilized forms. It focuses on the comparison between 3 different enzymatic membrane reactors for erythromycin degradation by esterase EreB. In the first configuration the free biocatalyst was confined in the reaction media by a ceramic membrane. In the two other cases, the enzyme was immobilized in the membrane either covalently grafted or adsorbed. Please click Additional Files below to see the full abstract

Sweep gas membrane distillation in a membrane contactor with metallic hollow fibers

This work revolves around the use of porous metal hollow fibers in membrane distillation. Various stages are covered, starting from membrane synthesis up to the testing of a pilot scale membrane module. Mechanically stable metal hollow fibers have been synthesized by phase inversion of a stainless steel particle loaded polymer solution, followed by thermal treatment to remove the polymer and sinter the particles together. The pore surface of the metal fibers has been made hydrophobic by functionalization with polydimethylsiloxane or stearic acid. A water evaporation flux of 0.2 kg h−1 m−2 was obtained at a feed water temperature of 333 K and a sweep gas flow rate of 135 L h−1 (Reair=2458) with pure water as feed. Under similar operating conditions, an evaporation flux of 0.14 kg h−1 m−2 was achieved when a 600 g L−1 sucrose solution was used as feed

Treatment of Wastewater Containing Pharmaceutical Micropollutants by Adsorption under Flow in Highly Porous Carbon Monoliths

Flow-through reactors made of highly porous hierarchical micro/meso/macroporous carbon monoliths (CM) were developed to decontaminate water containing pharmaceutical micropollutants (antibiotics). CM were prepared from hierarchical meso/macroporous silica monoliths as sacrificial templates after impregnation with sucrose as a carbon precursor, hydrothermal carbonization, and subsequent pyrolysis and dissolution of silica by NaOH. CM were fully characterized by nitrogen sorption at 77 K, Hg porosimetry, scanning electron microscopy, transmission electron microscopy, microtomography, permeability measurements, X-ray photoelectron spectroscopy, and chemical analysis. CM exhibit a large surface area (1058 m2 g–1), a large pore volume (6.5 mL g–1), high permeability, a homogeneous interconnected macropore network (22 μm), bimodal mesopores (6 and 15 nm), micropores (0.85 nm), and a large number of C═O and COO– groups. They are basic in water (pH 9) and negatively charged. First, adsorption of a single pharmaceutical molecule, tetracycline (TC), was studied. Isotherms of adsorption, kinetics, and diffusion were used to study the mechanism of adsorption on CM, and the process was found to be governed by electrostatic interactions. Then, a mixture of several antibiotics (ciprofloxacin, amoxicillin, sulfamethoxazole, and TC, 20 mg L–1 each) was used. The sorption capacity for antibiotics peaked at 815 mg g–1. In a recirculation flow configuration, with a flow rate of 1 mL min–1, CM could remove 93% of the antibiotics. These CM could represent a highly efficient solution for the purification of real wastewater containing pharmaceutical molecules, which are generally found at much lower concentrations (from a few nanograms per liter to micrograms per liter). Regeneration of CM was successfully achieved by washing with HCl (0.1 M)

Treatment of Wastewater Containing Pharmaceutical Micropollutants by Adsorption under Flow in Highly Porous Carbon Monoliths

Flow-through reactors made of highly porous hierarchical micro/meso/macroporous carbon monoliths (CM) were developed to decontaminate water containing pharmaceutical micropollutants (antibiotics). CM were prepared from hierarchical meso/macroporous silica monoliths as sacrificial templates after impregnation with sucrose as a carbon precursor, hydrothermal carbonization, and subsequent pyrolysis and dissolution of silica by NaOH. CM were fully characterized by nitrogen sorption at 77 K, Hg porosimetry, scanning electron microscopy, transmission electron microscopy, microtomography, permeability measurements, X-ray photoelectron spectroscopy, and chemical analysis. CM exhibit a large surface area (1058 m2 g–1), a large pore volume (6.5 mL g–1), high permeability, a homogeneous interconnected macropore network (22 μm), bimodal mesopores (6 and 15 nm), micropores (0.85 nm), and a large number of CO and COO– groups. They are basic in water (pH 9) and negatively charged. First, adsorption of a single pharmaceutical molecule, tetracycline (TC), was studied. Isotherms of adsorption, kinetics, and diffusion were used to study the mechanism of adsorption on CM, and the process was found to be governed by electrostatic interactions. Then, a mixture of several antibiotics (ciprofloxacin, amoxicillin, sulfamethoxazole, and TC, 20 mg L–1 each) was used. The sorption capacity for antibiotics peaked at 815 mg g–1. In a recirculation flow configuration, with a flow rate of 1 mL min–1, CM could remove 93% of the antibiotics. These CM could represent a highly efficient solution for the purification of real wastewater containing pharmaceutical molecules, which are generally found at much lower concentrations (from a few nanograms per liter to micrograms per liter). Regeneration of CM was successfully achieved by washing with HCl (0.1 M)

CO2 capture with room temperature ionic liquids; coupled absorption/desorption and single module absorption in membrane contactor

A membrane gas CO2 capture setup, based on the concept of single module absorption and single cycle coupled absorption/desorption, was developed in this work. Ionic liquids (ILs) 1-ethyl-3-methylimidazolium methylsulfate ([emim][MS]) and 1-ethyl-3-methylimidazolium dicyanamide ([emim][DCA]) were used as absorbents. The CO2 absorption rate decreased initially and reached to a nearly constant value achieving pseudo steady state. Coupled absorption/desorption revealed very high performance by retaining 82% and 66% absorption efficiency, for [emim][MS] and [emim][DCA], respectively, even after 70 min of operation. Mass transfer coefficients of the coupled absorption/desorption at pseudo steady state were 9 and 5 folds higher than single module absorption, for [emim][MS] and [emim][DCA], respectively. Parametric analysis for the membrane absorber outlet concentration and optimization of the parameters to achieve zero concentration at the membrane stripper outlet were studied in simulations. As a conclusion, coupled absorption/desorption in combination with ILs, can be considered very suitable for continuous post-combustion carbon capture

Report from Working Group 3: Beyond the Standard Model physics at the HL-LHC and HE-LHC

This is the third out of five chapters of the final report [1] of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC [2]. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as $3$ ab$^{-1}$ of data taken at a centre-of-mass energy of 14 TeV, and of a possible future upgrade, the High Energy (HE) LHC, defined as $15$ ab$^{-1}$ of data at a centre-of-mass energy of 27 TeV. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by $20-50\%$ on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will, generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics

Report from Working Group 3 : Beyond the Standard Model Physics at the HL-LHC and HE-LHC

CERN Yellow Reports: Monographs, vol 7 (2019)Contribution to: HL/HE-LHC WorkshopThis is the third out of five chapters of the final report [1] of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC [2]. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as $3$ ab$^{-1}$ of data taken at a centre-of-mass energy of 14 TeV, and of a possible future upgrade, the High Energy (HE) LHC, defined as $15$ ab$^{-1}$ of data at a centre-of-mass energy of 27 TeV. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by $20-50\%$ on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will, generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics