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A new coordination polymer, Zn‐(OC‐AMAM‐CO) CP, has been synthesized from Zn (II) as ionic node and 2,2′‐((1,2‐phenylenebis [azanediyl])bis (carbonyl))dibenzoic acid, (OC‐AMAM‐CO), as a new linker, where (OC‐AMAM‐CO) has been synthesized as an amide product through condensation reaction of phthalic acid and o‐phenylenediamine. The amide product (OC‐AMAM‐CO) and Zn‐(OC‐AMAM‐CO) CP were characterized via FTIR and PXRD analyses, and Zn‐(OC‐AMAM‐CO) CP was further characterized via SEM/EDX and XPS analyses. Moreover, DFT study was performed to shed light on the both structures of (OC‐AMAM‐CO) and Zn‐(OC‐AMAM‐CO). PXRD analysis revealed the successful syntheses of the new linker (OC‐AMAM‐CO) and Zn‐(OC‐AMAM‐CO) CP where the new CP is crystalline. DFT study revealed that the 3D topological structure assembled through coordination, π–π stacking, and hydrogen bonding. Zn‐(OC‐AMAM‐CO) CP was applied as an adsorbent for the removal of Cu (II) from water as it has abundant chelating groups that serve as adsorptive coordinating sites. Isotherm study revealed the obedience of Cu (II)/Zn‐(OC‐AMAM‐CO) CP adsorption system to Langmuir modeling with adsorption capacity of about 55 mg/g. A kinetic study showed that the rate of adsorption was a pseudo‐first‐order type. Further, adsorption process was found to be strongly diffusion dependent. [ABSTRACT FROM AUTHOR]

Cinnamon verum was used as a low‐cost precursor to produce microporous‐activated carbons with a high surface area (894 m2/g) and large total pore volume (0.49 cm3/g). Thermogravimetric analysis scanning electron microscopy, Fourier‐transform infrared spectroscopy, Brunauer–Emmett–Teller surface area, and pore size analyzer techniques were used to characterize the new sorbent. The new porous carbon's ability to remove chlorpyrifos (CPS), an organo‐phosphorus surrogate of ware gases and the active component in most insecticides and pesticides, has been assessed by a batch adsorption procedure. Different sorption factors such as initial CPS concentrations, contact time, pH, solution temperature, and sorbent dosage have been studied. The results show that the new sorbent could remove 100% of CPS at low concentrations of 20 ppm within 20 min of contact time under a favorable sorption process. CPS adsorption was found to be exothermic, and the adsorption capacity decreases with increasing temperature. Equilibrium results were modeled using three isotherm models: Langmuir, Freundlich, and Temkin. The Langmuir isotherm model was found to be the best model to represent the CPS adsorption data. The kinetic results were fitted to pseudo–first‐order, pseudo–second‐order, and intraparticle diffusion models and thoroughly followed the pseudo–second‐order kinetic model. Thermodynamic factors such as enthalpy (ΔHo), entropy (ΔSo), and free energy (ΔGo) were assessed. The negative values of ΔHo and ΔGo indicate the exothermic and spontaneous nature of the adsorption process. The sorbent from waste cinnamon bark was economically practical and eliminates organophosphorus compounds from aqueous solutions. [ABSTRACT FROM AUTHOR]

Ammonia gas is an irritating and corrosive gas commonly used in fertilizers, refrigerants and cleaners. In this work, a sensitive and selective nanocomposite film is fabricated on a quartz crystal microbalance (QCM) with hybrid TiO2–SnO2/multi-walled carbon nanotube (MWCNT) doped Cu-BTC for detection of trace amounts of ammonia under ambient conditions. Cu-BTC exhibits excellent porosity for gas sensing, but its poor stability in the presence of water and ammonia limits the long term viability. Hybrid TiO2–SnO2/MWCNT doping prevents the framework decomposition and improves longevity. The nanocomposite film is rapidly synthesized under ambient conditions using a facile intense pulsed light (IPL) technique to stimulate in situ growth. IPL also assists in the thermal conversion of anatase TiO2 to rutile TiO2. This functionalized nanocomposite film-based QCM sensor demonstrates ammonia gas sensing capability with a limit of detection estimated to be 0.77 ppm and strong stability even under humid conditions. The sensor exhibits reversibility during cyclic testing and a minimal drift suggesting that the reaction mechanism is primarily surface adsorption. Changes in the motional resistance and resonance frequency of the sensor can be linearly related to the ammonia gas concentration. [ABSTRACT FROM AUTHOR]

Novel anion-exchange electrospun fiber membranes of polycaprolactone doped with the cationic, cross-linked colesevelam polymer are reported. The weight fraction of cross-linked cationic colesevelam polymer, as the active phase within the PCL matrix, can readily be controlled in the synthesis of the mixed-matrix fibers (Cole@PCL), enabling optimization of the ion-exchange properties of the resulted membranes. This approach enabled adaptation of anion-exchange resins to a permeable, flexible membrane form, which is a significant advancement toward futuristic water treatment applications, demonstrated herein for the removal of trace contaminants, including nitrates and phosphates, as well as anionic dyes. The Cole@PCL membranes demonstrated the dependence of contaminant uptake on the weight percentage of colesevelam in the mixed-matrix membrane. An optimal 10 wt % of colesevelam was identified, demonstrating a staggering ion removal capacity of 155.8 mg/g for nitrate, 177.6 mg/g for phosphate, and 70 mg/g for Methyl Orange.