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Developing anion exchange membranes (AEMs) with superior chemical stability and high conductivity is a considerable challenge for the practical application in AEM fuel cells. Herein, novel ionic crosslinked AEMs from methylpyrrolidinium functionalized poly (vinyl benzyl chloride) (PVBC-MPy) and sulfonated poly(ether ether ketone) (sPEEK) were fabricated through a facile and gentle method. The PVBC-MPy ionomer with a superior alkaline stability is used as the hydroxide conductor, while the sPEEK polymer plays the role as a macromolecular crosslinker. The PVBC-MPy exhibited good compatibility with sPEEK without phase separation. The obtained PVBC-MPy/x%sPEEK membranes displayed excellent oxidative resistance toward the attack of radicals as demonstrated by Fenton test. Meanwhile, AEMs also exhibited low dimensional swellings, improved mechanical strength, high conductivity and superior alkaline stability simultaneously. The PVBC-MPy/10%sPEEK membrane exhibited a weight retention rate of 86% after the Fenton test for 180 h, a volume swelling of 45%, a tensile strength of 25.6 MPa at room temperature, an anion conductivity of 28 mS cm−1 at 80°C, and retained its initial conductivity of 86.4% after immersing in 1 M KOH at 80°C for 410 h. [ABSTRACT FROM AUTHOR]

Hazardous chemicals released from the petroleum-derived face mask can be inhaled by wearers and cause adverse health effects. Here, we first used headspace solid-phase microextraction coupled with GC-MS to comprehensively analyze the volatile organic compounds (VOCs) released from 26 types of face masks. The results showed that total concentrations and peak numbers ranged from 3.28 to 197 μg/mask and 81 to 162, respectively, for different types of mask. Also, light exposure could affect the chemical composition of VOCs, particularly increasing the concentrations of aldehydes, ketones, organic acids and esters. Of these detected VOCs, 142 substances were matched to a reported database of chemicals associated with plastic packaging; 30 substances were identified by the International Agency for Research on Cancer (IARC) as potential carcinogenic to humans; 6 substances were classified in the European Union as persistent, bioaccumulative, and toxic, or very persistent, very bioaccumulative substance. Reactive carbonyls were ubiquitous in masks, especially after exposure to light. The potential risk of VOCs released from the face masks were then accessed by assuming the extreme scenario that all the VOC residues were released into the breathing air within 3 h. The result showed that the average total concentration of VOCs (17 μg/m3) was below the criterion for hygienic air, but seven substances, 2-ethylhexan-1-ol, benzene, isophorone, heptanal, naphthalene, benzyl chloride, and 1,2-dichloropropane exceeded the non-cancer health guidelines for lifetime exposure. This finding suggested that specific regulations should be adopted to improve the chemical safety of face masks. [Display omitted] • Large amount of VOCs were detected from the face masks. • Light irradiation significantly affected the VOC release profile. • Hazardous VOCs released from the face masks were screened. • Seven compounds released from face masks were recognized as high-risk. [ABSTRACT FROM AUTHOR]

Cationic polyacrylates have efficient reverse demulsification performance and air flotation performance, which make them potentially viable for application in offshore oil fields. However, study of the relationship between their structure and performance is still lacking. In this paper, four compounds (benzyl chloride, 3-chloro-1-propanol, 3-chloro-1,2-propanediol and 3-chloro-2-hydroxytrimethylammonium chloride) were used to modify the copolymer of acrylate and tertiary amine monomer, and four cationic polyacrylates (CP-1, CP-2, CP-3 and CP-4) with different cationic unit structures were prepared. The hydrophilicity of the cationic units in these four cationic polyacrylates increased successively. The relationship between the cationic unit structure, interface properties and produced water treatment performance of products was studied. The results showed that CP-1 had the highest air flotation efficiency because it had the largest adsorption capacity on the surface of bubble and the strongest attractive force between oil droplets, while CP-2 had the highest reverse demulsification efficiency because it had the largest adsorption capacity on the surface of oil droplet and the strongest ability to reduce the elastic modulus of the O/W interface. The research results can provide a reference for chemical agent selection in the treatment of oilfield produced water. • Four cationic polyacrylates with different cationic units were prepared. • 5 mg/L CP-1 had the highest flotation efficiency of 81.3% among four polyacrylates. • 5 mg/L CP-2 had the highest reverse demulsification efficiency of 56.0%. [ABSTRACT FROM AUTHOR]

Density and speed of sound were measured earlier by us for binary liquid mixtures formed by Benzonitrile, Chlorobenzene, Benzyl chloride and Benzyl alcohol with Benzene at temperature range 298.15 to 313.15 K and atmospheric pressure over the whole concentration range. Pseudo-Gruneisen parameter and internal pressure were derived from the measured values of density and ultrasonic velocity. These values were compared with the theoretical values obtained by the utilization of Flory theory, Ramaswamy and Anbananthan model and model suggested by Glinski to predict the behavior of weakly interacting liquids. The observed properties derived from measured data were fitted to Redlich-Kister polynomial relation to estimate the binary coefficients and standard errors. Excess Pseudo-Gruneisen parameter for these binary mixtures was computed to study the molecular interactions involved in the liquid systems. [ABSTRACT FROM AUTHOR]

In this work, different amines (bifunctional, as diazabicyclo[2.2.2]octane (Dabco) and monofunctional, as N-methylimidazole or trimethylamine) were utilized for the amination of benzyl chloride-grafted polystyrene-b-poly(butadiene)-bpolystyrene triblock copolymers (SBS-g-VBC). The use of Dabco solutions in mixture with variable amounts of monoamine or at different concentration allowed to modulate the degree of crosslinking of the SBS-based membranes and their electrochemical parameters. More specifically, tuning Dabco concentration permitted the reduction of water uptake without significantly affecting ionic conductivity. [ABSTRACT FROM AUTHOR]

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The catalyst of AlCl3 immobilized on 7-Al2O3 with different pores was prepared and tested in the benzylation reaction of benzene with benzyl chloride to form diphenylmethane. Conventional homogeneous pure AlCl3 was also included for comparison especially on temperature. The experimental data of forming diphenylmethane for different reaction temperature and catalyst were gained by gas chromatography. The kinetics model of the reaction, in which internal diffusion factors were considered, was established. Then the parameters of diphenylmethane apparent formation rate constant, apparent activation energy and diffusion coefficient were obtained in a liquid-solid reaction system. The results indicate that the immobilized AlCl3 catalyst was found to be more selective but less active compared to pure AlCl3 due to its pore diffusion resistance. With the decrease of the pore diameter of the supports, the diffusion coefficient of the reaction decreases sharply. The internal diffusion resistance plays an important role in the activity of benzylation reaction of benzene with benzyl chloride to form diphenylmethane over the immobilized AlCl3 catalysts. [ABSTRACT FROM AUTHOR]

• The geometric and electronic attributes of violet phosphorene (VP) sheets are studied. • The surface assimilating attributes of VP upon benzyl chloride and chlorobenzene adsorption is explored. • The Bader charge transfer and adsorption energy of VP upon adsorption of benzyl chloride and chlorobenzene are studied. • The results confirms that VP can be used as a base component to detect benzyl chloride and chlorobenzene molecules. In the present model, we aim to sense the availability of organic compounds, benzyl chloride and chlorobenzene with the help of violet phosphorene (VP). In order to enunciate the utilization of VP as a chief component in detecting the aforementioned volatile organic compounds, ATK-VNL package is applied to scrutinize the geometric and electronic attributes of VP. The electronic properties like band structure, electron density and projected density of states (DOS) spectrum are estimated for pristine and organic compounds surface assimilated VP. Initially, the stability of VP is affirmed with the aid of formation energy and the work is carried out. In addition, the surface assimilating parameters like average energy gap variation, Bader charge transfer, and adsorption energy are computed to validate our proposed work. As a whole, this work ensures the employment of VP as a base component to detect the availability of volatile organic compounds benzyl chloride and chlorobenzene. [ABSTRACT FROM AUTHOR]

The benzylation of benzene by benzyl chloride over a series of Thallium-containing mesoporous silicas with different Tl contents has been investigated. These materials (Tl-HMS-n) have been characterized by chemical analysis, N 2 adsorption/desorption isotherm and X-ray diffraction (XRD). The mesoporous Thallium-containing materials showed both high activity and high selectivity for the benzylation of benzene. More interesting is the observation that these catalysts are always active and selective for large molecules like naphthenic compounds such as methoxynaphthalene. [ABSTRACT FROM AUTHOR]

The alkylation of toluene, reaction employing benzyl chloride as the alkylating agent over basic hydrotalcite materials: Fe–Mg–Al-LDH prepared by different synthesis methods, including the method of co-precipitation, impregnation and a new method called the method of intercalation by anion exchange in the lamellar space of the host structure LDH. Our prepared solids were characterized by chemical analysis, XRD analysis, BET method and thermogravimetric analysis (TGA) and tested in the alkylation of toluene by benzyl chloride reaction. Fe–Mg–Al-LDH clay without or with calcination (at 773 K) has been investigated. The catalyst derived from the hydrotalcite by its calcination at 773 K shows high catalytic activity for the alkylation of toluene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the oxides of iron on the catalyst surface. [ABSTRACT FROM AUTHOR]