Amidohydroxylated polyester with biophotoactivity along with retarding alkali hydrolysis through in situ synthesis of Cu/Cu2O nanoparticles using diethanolamine

In this research, polyester fabric was modified through in situ synthesis of Cu/Cu₂O nanoparticles (NPs) in one single step processing using diethanolamine. This introduced amide and hydroxyl active groups on the polyester surface, adjusted pH, aminolyzed, and improved the surface activity of polyester. Copper sulfate was used as precursor, sodium hypophosphite as a reducing agent and polyvinylpyrrolidone as a stabilizer in a chemical reduction route at boil as a facile and cost‐effective approach. The central composite design was also utilized to optimize the processing conditions and study the effect of each variables on the weight gain, color change, and wettability of the treated fabrics. FESEM and mapping, EDX, XRD, and FTIR analysis confirmed effective assembling of Cu/Cu₂O NPs on the amidohydroxylated polyester surface. The optimum treated fabric showed excellent antibacterial properties on both Staphylococcus aureus and Escherichia coli. In addition, a very good photocatalytic activity towards degradation of methylene blue solution obtained after 24 h sunlight irradiation. Further, the hydrophilicity, mechanical properties and stability of the treated fabrics in concentrated sodium hydroxide improved through formation of amidohydroxyl active groups, amidoester cross‐linking and nanocross‐linking within polymeric chains through in situ synthesis of Cu/Cu₂O. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44856.     

High‐performance carboxylate superplasticizers for concretes: Interplay between the polymerization temperature and properties

Polycarboxylate superplasticizers based on acrylic acid (AA) and maleic anhydride (MAn) were synthesized via free‐radical copolymerization with an ethylene glycol monomer and characterized. The copolymerization temperature (ranging from 50 to 90 °C) appeared to be the key operating factor governing the chemical structure of the superplasticizers. The chemical structures of the products were analyzed by gel permeation chromatography, whereas an optimized sample was further analyzed by Fourier transform infrared spectroscopy and ¹H‐NMR. Superplasticizers of the AA and MAn classes were then incorporated into concrete, and their performances were measured by slump and slump loss tests, where a large dependency of the microstructure on the synthesis temperature was recognized. The optimum temperatures were found to be 50 and 80 °C for the AA and MAn modifiers, respectively. At their own optimum temperatures, the AA and MAn superplasticizer revealed slump losses from 23 to 4 cm and 15 to 5 cm, respectively, after 45 min. The chemical structures of the plasticizers were patterned illustratively to speculate the performance of each superplasticizer according to changes that took place in the backbone length and side‐chain density. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44908.     

General optimization model for the energy planning of industries including renewable energy: A case study on oil sands

A multi‐period optimization model is developed for the energy procurement planning of industries including renewable energy. The model is developed with the objective of identifying the optimal set of energy supply technologies to satisfy a set of demands (e.g., power, heat, hydrogen, etc.) and emission targets at minimum cost. Time dependent parameters are incorporated in the model formulation, including demands, fuel prices, emission targets, carbon tax, lead time, etc. The model is applied to a case study based on the oil sands operations over the planning period 2015–2050. Various production alternatives were incorporated, including renewable, nuclear, conventional and gasification of alternative fuels. The results obtained indicated that the energy optimization model is a practical tool that can be utilized for identifying the key parameters that affect the operations of energy‐intensive industrial operations, and can further assist in the planning and scheduling of the energy for these industries. © 2016 American Institute of Chemical Engineers AIChE J, 63: 610–638, 2017     

Integration of biofuels intermediates production and nutrients recycling in the processing of a marine algae

The cost‐effective production of liquid biofuels from microalgae is limited by several factors such as recovery of the lipid fractions as well as nutrients management. Flash hydrolysis, a rapid hydrothermal process, has been successfully applied to fractionate the microalgal biomass into solid biofuels intermediates while recovering a large amount of the nutrients in the aqueous phase (hydrolyzate) in a continuous flow reactor. The aim of the work is to enhance the quality of a high‐ash containing marine algae Nannochloropsis gaditana as biofuel feedstock while recycling nutrients directly for algae cultivation. Characterization of products demonstrated an increase in extractable lipids from 33.5 to 65.5 wt % (dry basis) while retaining the same fatty acid methyl ester profile, in addition to diminution of more than 70 wt % of ash compared to raw microalgae. Moreover, the hydrolyzate was directly used to grow a microalga of the same genus. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1494–1502, 2017     

Triboelectric charging of monodisperse particles in fluidized beds

To investigate the interplay between particle charging and hydrodynamics in fluidized beds, models for triboelectric charging and electrostatic forces were built into a computational fluid dynamics‐discrete element method model. Charge transfer was governed by the difference in effective work function between contacting materials as well as the electric field at the point of contact. Monodisperse particles were fluidized with an effective work function difference between the particles and the conducting walls. For smaller work function differences, hydrodynamics were not changed significantly as compared with an uncharged case. In these simulations, the average charge saturated at a value much lower than the value anticipated based on the work function difference, and a unimodal distribution of charges was observed. For larger work function differences, particles stuck to walls and bed height oscillations due to slugging were less pronounced. For these cases, a bimodal distribution of charges emerged due to effects from strong electric fields. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1872–1891, 2017     

Investigation of the effect of magnetic field on mass transfer parameters of CO2 absorption using Fe3O4‐water nanofluid

In this study, the enhancement of physical absorption of carbon dioxide by Fe₃O₄‐water nanofluid under the influence of AC and DC magnetic fields was investigated. Furthermore, a gas‐liquid mass transfer model for single bubble systems was applied to predict mass transfer parameters. The coated Fe₃O₄ nanoparticles were prepared using co‐percipitation method. The results from characterization indicated that the nanoparticles surfaces were covered with hydroxyl groups and nanoparticles diameter were 10–13 nm. The findings showed that the mass transfer rate and solubility of carbon dioxide in magnetic nanofluid increased with an increase in the magnetic field strength. Results indicated that the enhancement of carbon dioxide solubility and average molar flux gas into liquid phase, particularly in the case of AC magnetic field. Moreover, results demonstrated that mass diffusivity of CO₂ in nanofluid and renewal surface factor increased when the intensity of the field increased and consequently diffusion layer thickness decreased. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2176–2186, 2017     

A mathematical model for optimal compression costs in the hydrogen networks for the petroleum refineries

Hydrogen network design is an important step in hydrogen management of a petroleum refinery that manages the hydrogen distribution and consumption in a cost‐effective manner. While most works in this area have primarily focused on minimization of fresh hydrogen requirement and hydrogen purification aspects, very few works have dealt the issue of compression costs in hydrogen network designs. This work proposes a new mathematical model for synthesizing a hydrogen network with minimum compression costs. In contrast to the existing literature, this model uses stream‐dependent properties and realistic compressor cost correlations to determine the compression duty and costs, respectively. Tests on literature examples show that our model is flexible and gives reasonably favorable solutions than the previous models. Furthermore, the usefulness of understanding the trade‐offs between the number of compressors and compression duty and the importance of using stream‐dependent conditions in estimating compression costs are also highlighted in this work. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3925–3943, 2017     

Lead(II)‐ion removal by ethylenediaminetetraacetic acid ligand functionalized magnetic chitosan–aluminum oxide–iron oxide nanoadsorbents and microadsorbents: Equilibrium,kinetics, and thermodynamics

Novel nanosized and microsized chitosan–Al₂O₃–Fe₃O₄ (CANF and CAMF, respectively) adsorbents were functionalized with ethylenediaminetetraacetic acid (EDTA) ligands and applied to the removal of Pb(II) ions. The prepared adsorbents were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–Teller analysis, and their adsorption potentials were investigated with Pb(II) as a target metal under various experimental conditions. Our results show that the EDTA functionalization of CANF and CAMF increased their adsorption capacities about 31.5 and 38 times, respectively. The optimum dosage obtained was 1.0 g/L for both EDTA‐functionalized adsorbents, and the maximum adsorption took place at pH = 5.3. The kinetic results revealed that the adsorption obeyed the pseudo‐second‐order model and that the pore diffusion process played a key role in the adsorption kinetics. Also, the results of equilibrium isotherms indicate the good fit of the experimental data by the Langmuir isotherm model under the studied concentration and temperature ranges, and the adsorptions of Pb(II) ions from aqueous solution followed the monolayer coverage of the adsorbents. The maximum Pb(II)‐ion adsorption capacities of EDTA–CANF and EDTA–CAMF were 160 and 157 mg/g, respectively. These metal‐loaded adsorbents could be readily recovered from aqueous solution by magnetic separation and reused. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44360.     

First Application of Newly Developed FT-NIR Spectroscopic Methodology to Predict Authenticity of Extra Virgin Olive Oil Retail Products in the USA

Economically motivated adulteration (EMA) of extra virgin olive oils (EVOO) has been a worldwide problem and a concern for government regulators for a long time. The US Food and Drug Administration (FDA) is mandated to protect the US public against intentional adulteration of foods and has jurisdiction over deceptive label declarations. To detect EMA of olive oil and address food safety vulnerabilities, we used a previously developed rapid screening methodology to authenticate EVOO. For the first time, a recently developed FT-NIR spectroscopic methodology in conjunction with partial least squares analysis was applied to commercial products labeled EVOO purchased in College Park, MD, USA to rapidly predict whether they are authentic, potentially mixed with refined olive oil (RO) or other vegetable oil(s), or are of lower quality. Of the 88 commercial products labeled EVOO that were assessed according to published specified ranges, 33 (37.5%) satisfied the three published FT-NIR requirements identified for authentic EVOO products which included the purity test. This test was based on limits established for the contents of three potential adulterants, oils high in linoleic acid (OH-LNA), oils high in oleic acid (OH-OLA), palm olein (PO), and/or RO. The remaining 55 samples (62.5%) did not meet one or more of the criteria established for authentic EVOO. The breakdown of the 55 products was EVOO potentially mixed with OH-LNA (25.5%), OH-OLA (10.9%), PO (5.4%), RO (25.5%), or a combination of any of these four (32.7%). If assessments had been based strictly on whether the fatty acid composition was within the established ranges set by the International Olive Council (IOC), less than 10% would have been identified as non-EVOO. These findings are significant not only because they were consistent with previously published data based on the results of two sensory panels that were accredited by IOC but more importantly each measurement/analysis was accomplished in less than 5 min.     

Synthesis of water dispersible reduced graphene oxide via supramolecular complexation with modified β-cyclodextrin

A noncovalent functionalization of the edges of reduced graphene oxide (RGO) with β-cyclodextrin-graft-hyperbranched polyglycerol (β-CD-g-HPG) was successfully performed via a host-guest interaction. The results showed that β-CD-g-HPG disperses the graphene sheets better than pure β-CD or HPG. The resulted supramolecular structure is stable in neutral water medium more than one week. However, in acidic medium the host-guest interaction is collapsed and graphene nanosheets precipitate.