Benzene Polymer Research Articles

Ternary heterojunction of cross-linked benzene Polymer/Bi2MoO6-Graphene oxide catalysts promote efficient adsorption and photocatalytic removal of oxytetracycline

Antibiotics are refractory degradable organic pollutants that present a significant hazard to water environments. In this work, a ternary composite (KB/BMO-GO) comprising of graphene oxide (GO), Bi2MoO6 (BMO), and a cross-linked benzene polymer (KB) was synthesized and applied to promote the synergistic adsorption-photocatalytic degradation of the refractory pollutant, oxytetracycline (OTC). The inclusion of GO and KB in the composite enhanced the OTC adsorption performance of the catalysts, and the construction of Z-scheme heterojunction promoted the photogenerated charge separation efficiency and broadened the range of light absorption, thereby enhancing the photocatalytic performance. Moreover, we compared the performance of catalysts loaded with different mass ratios of KB (x% KB/BMO-GO). Among them, the 15 % KB/BMO-GO catalyst sample had the best OTC degradation performance. Specifically, 15 % KB/BMO-GO could adsorb 69.7 % of OTC in 30 min, reaching an OTC degradation rate of 93.3 % under visible light irradiation. h+ and 1O2 are the main active substances in the photocatalytic process. In addition, the catalysts are acid-alkali and salt-resistant, as well as good reusability. This study provides a valuable reference for the preparation of highly efficient photocatalysts for synergistic adsorption-photodegradation processes.

Utilization of the through-space effect to design donor-acceptor systems of pyrrole, indole, isoindole, azulene and aniline.

Molecular electrostatic potential (MESP) topology analysis reveals the underlying phenomenon of the through-space effect (TSE), which imparts electron donor-acceptor properties to a wide range of chemical systems, including derivatives of pyrrole, indole, isoindole, azulene, and aniline. The TSE is inherent in pyrrole owing to the strong polarization of electron density (PoED) from the formally positively charged N-center to the C3C4 bonding region. The N → C3C4 directional nature of the TSE has been effectively employed to design molecules with high electronic polarization, such as bipyrroles, polypyrroles, phenyl pyrroles, multi-pyrrolyl systems and N-doped nanographenes. In core-expanded structures, the direction of electron flow from pyrrole units towards the core leads to highly electron-rich systems, while the opposite arrangement results in highly electron-deficient systems. Similarly, the MESP analysis reveals the presence of the TSE in azulene, indole, isoindole, and aniline. Oligomeric chains of these systems are designed in such a way that the direction of electron flow is consistent across each monomer, leading to substantial electronic polarization between the first and last monomer units. Notably, these designed systems exhibit strong donor-acceptor characteristics despite the absence of explicit donor and acceptor moieties, which is supported by FMO analysis, APT charge analysis, NMR data and λmax data. Among the systems studied, the TSEs of many experimentally known systems (bipyrroles, phenyl pyrroles, hexapyrrolylbenzene, octapyrrolylnaphthalene, decapyrrolylcorannulene, polyindoles, polyazulenes, etc.) are unraveled for the first time, while numerous new systems (polypyrroles, polyisoindoles, and amino-substituted benzene polymers) are predicted to be promising materials for the creation of donor-acceptor systems. These findings demonstrate the potential of the TSE in molecular design and provide new avenues for creating functional materials.

Solid phase extraction of ocean dissolved organic matter with PPL cartridges: efficiency and selectivity

Our current knowledge of the chemical composition of ocean dissolved organic matter (DOM) is limited, mainly because of its extreme molecular diversity, low concentration of individual compounds and the elevated ionic strength of ocean waters. As a result, many analytical methods require a previous extraction step. The efficiency and selectivity of the extraction method defines the representativeness of the extracted DOM fraction. Nowadays, the most widespread procedure for concentrating DOM is solid phase extraction (SPE) using styrene divinyl benzene polymer cartridges (PPL). Here, we investigate the effect of SPE-PPL on DOM elemental and optical properties to assess the efficiency and selectivity of this extraction method on water samples from the main intermediate and deep water masses of Arctic, Mediterranean and Antarctic origin present in the Cape Vert Frontal Zone (CVFZ, NW Africa). Furthermore, North and South Atlantic Central waters converge in this area and coastal DOM is injected by the giant upwelling filament of Cape Blanc. On one side, the colored fraction of DOM (CDOM) presented extraction efficiencies comparable to that of the bulk dissolved organic carbon (DOC), but decreased significantly with increasing wavelength, suggesting an affinity of PPL cartridges for low molecular weight organic compounds. While the protein-like fluorescent fraction of DOM (FDOM) was also extracted with the same efficiency than DOC, the extraction efficiency of the humic-like fraction was comparatively much higher. On the other side, dissolved organic nitrogen (DON) extraction efficiencies were about half that of DOC. These contrasting extraction efficiencies of the different DOM pools indicated that the extracts were enriched in N-poor, low molecular weight and recalcitrant DOM, therefore showing less variability than the corresponding bulk DOM. Furthermore, DOC, DON, CDOM and FDOM extracted were not homogeneous through the water column but displayed certain significant differences among water masses in both efficiency and selectivity.

A Novel POP-Ni Catalyst Derived from PBTP for Ambient Fixation of CO2 into Cyclic Carbonates.

The immobilization of homogeneous catalysts has always been a hot issue in the field of catalysis. In this paper, in an attempt to immobilize the homogeneous [Ni(Me6Tren)X]X (X = I, Br, Cl)-type catalyst with porous organic polymer (POP), the heterogeneous catalyst PBTP-Me6Tren(Ni) (POP-Ni) was designed and constructed by quaternization of the porous bromomethyl benzene polymer (PBTP) with tri[2-(dimethylamino)ethyl]amine (Me6Tren) followed by coordination of the Ni(II) Lewis acidic center. Evaluation of the performance of the POP-Ni catalyst found it was able to catalyze the CO2 cycloaddition with epichlorohydrin in N,N-dimethylformamide (DMF), affording 97.5% yield with 99% selectivity of chloropropylene carbonate under ambient conditions (80 °C, CO2 balloon). The excellent catalytic performance of POP-Ni could be attributed to its porous properties, the intramolecular synergy between Lewis acid Ni(II) and nucleophilic Br anion, and the efficient adsorption of CO2 by the multiamines Me6Tren. In addition, POP-Ni can be conveniently recovered through simple centrifugation, and up to 91.8% yield can be obtained on the sixth run. This research provided a facile approach to multifunctional POP-supported Ni(II) catalysts and may find promising application for sustainable and green synthesis of cyclic carbonates.

Molecular composition and chemodiversity of dissolved organic matter in wastewater sludge via Fourier transform ion cyclotron resonance mass spectrometry: Effects of extraction methods and electrospray ionization modes

High-resolution mass spectrometry was extensively applied in molecular composition and transformation pathways of dissolved organic matter (DOM) in wastewater sludge treatments. Sample pretreatment methods and electrospray ionization (ESI) modes significant affect the accuracy of molecular characterization for DOM. This study investigated the effects of pretreatment methods (styrene divinyl benzene polymer (PPL), octadecyl (C18), and electrodialysis (ED)) on molecular characteristics of DOM in two typical wastewater sludges (waste activated sludge (WAS) and anaerobic digestion sludge (ADS)) analyzed by FT-ICR MS in both positive ESI (ESI (+)) and negative ESI (ESI (−)) modes. The results indicated that ED pretreatment exhibited the highest recovery rate of 70% ‒ 95% for sludge-derived DOM. ED and PPL performed well in recovering the different sludge-derived DOM with a high similarity of molecular characteristics (e.g., lipids, proteins/aliphatic, and lignins/CRAM-like), and the C18 method was ineffective in extracting carbohydrates, unsaturated hydrocarbons, and amino sugars. In addition, compared with single ESI (−) analysis mode, the molecular number identified by ESI (+) analysis mode was increased by 200%, especially, more unsaturated hydrocarbons and N-containing compounds were detected. Except for biogenic DOM, plenty of emerging containments (ECs) in sludge-derived DOM were identified; ESI (−) mode was more effectively in recognizing the alkyl benzene sulfonic acids (e.g., anionic surfactants); and ESI (+) mode was more effectively for plasticizers identification, for example, dioctyl terephthalate and dibutyl phthalate. This study illustrated that ED pretreatment coupled with FT-ICR MS in dual ESI modes could give more insights in complexed molecular information for DOM in wastewater sludge, and provides a theoretical basis for subsequent sludge treatments and disposals.

SYNTHESIS OF ACTIVATED CARBON FROM STYRENE DIVINYL BENZENE POLYMER RESIN

The current study focuses on the synthesis of activated carbon from styrene divinyl benzene polymer (SDVB) resins using carbonization followed by oxidation using CO<sub>2</sub> as the activating agent. The effect of several synthesis parameters including N<sub>2</sub> gas flow rate, temperature, rate of heating or ramp, time during the carbonization process, as well as the CO<sub>2</sub> gas flow rate, temperature, and time during the activation process on the textural properties of the obtained carbon sample, like surface area and pore volume, has been investigated. The optimum parameters established for the carbonization process are 300 ml/min as the N<sub>2</sub> gas flow rate, 700°C as the temperature, and 6°C/min of the ramp. Increasing gas flowrates and temperature only to certain range results in higher specific surface area (SSA) obtained during carbonization, whereas the decreased rate of heating shows a positive effect in SSA of the obtained carbon sample. The optimum parameters obtained for the activation process are 100 ml/min of N<sub>2</sub> gas flow rate, 100 ml/min as the CO<sub>2</sub> gas flow rate, 700°C as the temperature and 6°C/min of the ramp. The maximum surface area obtained at the optimum synthesis conditions is 881 m<sup>2</sup>/g. It is observed that during activation, lower temperature and intermediate treatment (1 h) resulted in the maximum SSA of the activated carbon. Overall, it can be said that a protocol for obtaining the maximum surface area of activated carbon has been developed based on the in-depth study of carbonization and activation during the synthesis of activated carbon.

Enhanced EDC removal from water through electron beam-mediated adsorber particle integration in microfiltration membranes.

The existence of endocrine disrupting chemicals (EDCs) in water and wastewater gives rise to significant environmental concerns. Conventional treatment approaches demonstrate limited capacity for EDC removal. Thus, incorporation of advanced separation procedures becomes essential to enhance the efficiency of EDC removal. In this work, adsorber composite microfiltration polyethersulfone membranes embedded with divinyl benzene polymer particles were created. These membranes were designed for effectively removing a variety of EDCs from water. The adsorber particles were synthesized using precipitation polymerization. Subsequently, they were integrated into the membrane scaffold through a phase inversion process. The technique of electron beam irradiation was applied for the covalent immobilization of particles within the membrane scaffold. Standard characterization procedures were carried out (i.e., water permeance, contact angle, X-ray photoelectron spectroscopy and scanning electron microscopy) to gain a deep understanding of the synthesized membrane properties. Dynamic adsorption experiments demonstrated the excellent capability of the synthesized composite membranes to effectively remove EDCs from water. Particularly, among the various target molecules examined, testosterone stands out with the most remarkable enhancement, presenting an adsorption loading of 220 mg m-2. This is an impressive 26-fold increase in the adsorption when compared to the performance of the pristine membrane. Similarly, androst-4-ene-3,17-dione exhibited an 18-fold improvement in adsorption capacity in comparison to the pristine membrane. The composite membranes also exhibited significant adsorption capacities for other key compounds, including 17β-estradiol, equilin, and bisphenol-A. With the implementation of an effective regeneration procedure, the composite membranes were put to use for adsorption over three consecutive cycles without any decline in their adsorption capacity.

The bio- and thermal lability of dissolved organic matter as revealed by high-resolution mass spectrometry and thermal chemical analyses

It is critical to understand the chemical structures and lability of dissolved organic matter (DOM) in aquatic environments, as DOM represents one of the largest reduced carbon pools on earth. To achieve a comprehensive view of its composition and reactivity, DOM from both riverine and coastal waters were concurrently extracted via both ultrafiltration and modified styrene divinyl benzene polymer (PPL) based solid-phase-extraction (SPE), and further compared through multi-dimensional angles, including elemental analysis, total hydrolyzable amino acid composition, high-resolution liquid chromatography mass spectrometry (under both electrospray ionization modes), and thermochemical analysis. With a very low percentage (< 5%) of shared molecules, ultrafiltered-DOM (UDOM) and SPE-extracted DOM (SPEDOM) showed distinct differences in their bio- and thermal labilities. SPEDOM not only contained more “degraded” biomarkers, such as glycine, β-alanine, and γ-aminobutyric acid, but was also dominated by a higher abundance of more bio-recalcitrant lignin-like structures. Furthermore, thermogravimetric analysis revealed a higher activation energy of SPEDOM (138.8 ± 0.5 kJ·mol−1) than that of UDOM (125.4 ± 2.8 kJ·mol−1), suggesting that SPEDOM is more thermally recalcitrant than UDOM. Consistently, thermal slicing ramped pyrolysis showed a lower percentage of recalcitrant pyrolyzates (e.g., aromatic and phenol structures), but a higher contribution of labile compound classes (e.g., aliphatic structures) in UDOM, as well as a higher diversity of pyrolyzates from UDOM than SPEDOM. Taken together, our results demonstrated a highly heterogeneous nature in DOM composition and distinctly different bio- and thermal labilities between UDOM and SPEDOM, indicating that characterization of different fractions of DOM is needed for a comprehensive evaluation of natural DOM.

Interaction mechanism between cellulose and hemicellulose during the hydrothermal carbonization of lignocellulosic biomass

AbstractThe fuel properties of the solid product obtained from hydrothermal carbonization (HTC) are substantially influenced by the interaction reactions of the lignocellulose components. This study focused on the interaction reactions of cellulose and hemicellulose (represented by glucose and xylose, respectively) and the formation mechanism of the hydrochar through experiments and density functional theory methods. Results indicated that furfural was the main intermediate product of xylose and then converted into benzenes, which were seldom produced from the hydrothermal conversion of glucose. When glucose and xylose were co‐carbonized hydrothermally, more benzenes were generated because glucose and xylose exhibited a synergistic effect in forming alkenes, which were then cracked remarkably into C2H2. Furthermore, C2H2 reacted with furan that transformed from furfural and formed benzenes. The aqueous product of co‐HTC also contained a high concentration of 5‐hydroxymethylfurfural (5‐HMF). The 5‐HMF could polymerize with benzenes and furfural to form insoluble furan−benzene polymers, gradually aggregating into organic micronucleus. Subsequently, 5‐HMF, furfural, and benzenes in the aqueous phase were immobilized on the surface of the organic micronucleus through surface binding sites, eventually causing the growth of organic micronucleus into hydrochar particles. The polymerization between furan−benzene polymers could also increase the aromatization degree of the hydrochar, thereby enhancing the energy density of the hydrochar.

Аналіз обсягу хімічного виробництва українських коксохімічних підприємств у 2020 році

There has been carried out an analysis of the volume of chemical production for 2020 of eight Ukrainian coking enterprises and industries that were located in the territory controlled by Ukraine. It is shown that the maximum number of chemical products captured from coke oven gas accounted for anhydrous coal tar (419.1 thousand tons), crude benzene processing products - for commercial benzene (3.7 thousand tons), coal tar processing products - for coal tar pitch (96.4 thousand tons). Compared to 2019, the maximum increase in production volume in 2020 was accounted for by benzene polymers (by 4.5 times), technical solvent (by 2 times), distillation residues (by 2 times), head fraction (not produced in 2019), anthracene fraction (1.5 times), the maximum decline - for sulfuric acid (1.2 times), concrete mix plasticizers (not produced) and light-medium oil (1.3 times). On average for enterprises: out of 1 ton of dry charge, the yield of coal tar was 3.45 %, ammonia - 0.33 %, crude benzene - 0.68 %, and the maximum yield of the total consumption of raw materials fell on technical benzene - 58.3 % and medium-temperature pitch - 28.4 %. The properties of the same chemical products produced at different enterprises corresponded to different brands or grades, which is explained by the difference both in the quality of raw materials and in the features of production processes. Chemical products of coke companies were used in various industries as finished products or raw materials. Due to the destruction and damage of coke enterprises that were under the influence of hostilities or the disruption of the logistics supply of raw materials and energy resources, the issue of the ability of domestic coke enterprises to produce products becomes very relevant. The analysis given in the article should be used to assess the damage caused to domestic enterprises by the armed aggression of the Russian Federation. Key words: analysis, coke production, chemical products, coal tar, ammonium sulfate, benzene, sulfuric acid, coal tar pitch, coal oils, phenolates. Corresponding author: S.V. Chaplianko, e-mail: chaplianko_sv@ukr.net

Development of a low-cost portable aroma sensing system for identifying artificially ripened mango

Identification of naturally ripened mango using a pocket-friendly, portable aroma detection system (Aroma e-Sense) has been presented in this work. The study found 2, 5-Dimethyl-4-hydroxy-3(2 H)-furanone (DHF), a biomarker of artificially ripened (AR) mango. Hereto, a DHF imprinted polymer coupled to a quartz crystal microbalance (DHFIP-QCM) sensor has been fabricated to detect the important flavonoids. Aroma e-Sense with two modules, viz. DHFIP-QCM sensor, and signal processing module comprises of the crystal oscillator (10 MHz) synchronized with a frequency counter module, display module followed by storage module. The DHFIP-QCM sensor was designed using synthesized methacrylic acid-divinyl benzene polymer as sensing film. The developed Aroma eSense possesses significant repeatability (99.50 %), reproducibility (98.60 %), and stability towards DHF. Further, the developed system has been validated with standardized gas chromatography. Moreover, the Aroma e-Sense was found to be applicable to ensure whether mangoes are carbide treated or not.

Formation of helical polyphenyl nanostructures on carbon nanotubes

In this manuscript, helical polyphenyl (PP) nanostructures were formed on single-wall carbon nanotubes (SWCNT) through self-assemble process which was investigated by a molecular dynamics simulation. The results displayed that the linear polyphenyl changed into helical structure and finally a core–shell structure was formed. The formation mechanism of whole process was also exhibited. Furthermore, some influence factors such as the initial angle between polyphenyl chain and nanotube axis, the diameter of carbon nanotube were also displayed. Moreover, the interactions between different halogenated benzene polymer and carbon nanotube were also studied. The new geometrical structures between polyphenyl and single-wall carbon nanotubes may attract more attention in chemical functionalization and helical polymer synthesis, which may be helpful for fabricating nanoscale devices.

Two-step direct heteroarylation reaction towards 2,5-bis(alkoxy)benzene polymer for organic field-effect transistors processed with tetrahydrofuran

A 2,5-bis(alkoxy)benzene polymer POB-TNT has been newly designed and synthesized via very convenient two-step direct heteroarylation reaction. Its physicochemical properties have been investigated. POB-TNT demonstrates typical [Formula: see text]-type carrier transport characteristic in unencapsulated bottom-gate and top-contact organic field-effect transistors (OFETs) processed with relatively green tetrahydrofuran solvent. The results highlight a readily accessible and low-cost-oriented polymer semiconductor for non-halogenated solvent-processed OFET application.

Thermal transports of one-dimensional ultrathin carbon structures

Carbon atomic chain, linear benzene polymers, and carbon nanothreads are all one-dimensional (1D) ultrathin carbon structures. They possess excellent electronic and mechanical properties; however, their thermal transport properties have been rarely explored. Here, we systematically study their thermal conductance by combining the nonequilibrium Green’s function and force field methods. The thermal conductance varies from 0.24 to 1.00 nW K−1 at 300 K, and phonon transport in the linear benzene polymers and carbon nanothreads is strongly dependent on the connectivity styles between the benzene rings. We propose a simple 1D model, namely force-constant model, that explains the complicated transport processes in these structures. Our study not only reveals intrinsic mechanisms of phonon transport in these carbon structures, but also provides an effective method to analyze thermal properties of other 1D ultrathin structures made of only several atomic chains.

Simultaneous voltammetric analysis of lead, copper and mercury ions by carbon paste electrode based on 1-(3-aminopropyl) imidazole modified polymer

ABSTRACTIn this study, a carbon paste electrode modified with a novel 1-(3-aminopropyl) imidazole functionalised crosslinked chlorosulfonated poly(styrene)-divinyl benzene polymer was used for selective and sensitive determination of the trace amounts of Pb2+, Cu2+ and Hg2+ ions by square wave anodic stripping voltammetry. The effect of some parameters such as paste composition, pH, preconcentration time, reduction potential and time, type of supporting electrolyte and potential scan rate on the determination of metal ions were investigated to find the optimal conditions. The effective open-circuit accumulation of the studied metal ions was succeeded only by the modification of the carbon paste electrode with functional polymer. For 6 min open-circuit preconcentration, the detection limit of Pb2+, Cu2+ and Hg2+ was found to be 5, 9 and 14 µgL−1, respectively at 100 mVs−1. The results confirmed that the lower concentration levels of these trace metal ions can be determined with the increase of preconcentration time and/or potential scan rate. Good detection limits and large dynamic concentration ranges were also obtained for their binary and ternary mixtures. The optimised method was successively applied to determine the concentration of Pb2+, Cu2+ ions in the tap water sample and Cu2+ ion in the waste water sample in the presence of possible interfering species (RSD<1%, recoveries 96–110% for 4 min preconcentration).

Amino acid-imprinted polymers as highly selective CO2 capture materials

The recent atmospheric concentration of CO2 increase to 400 ppm is a cause of global climate change. There is therefore an urgent need for selective and cost-effective CO2 capture technologies. Fossil fuel consumption during energy production and transportation are two major sources of CO2 emission into the atmosphere. The capture of CO2 selectively from gaseous mixtures using reusable adsorbent is thus a challenge. In this article, we report that nanoparticles functionalized with imprinting of amino acids exhibit a significant increase in the selective adsorption capacities of CO2 in a gaseous mixture. Molecular imprinting of taurine in the vinylbenzyl chloride-co-divinyl benzene polymer formed cavities of 1–3 nm size and introduced –SOOH and –N–H functionalities, resulting in a very high CO2 adsorption capacity of 5.67 mmol g−1 at 30 °C/1 bar. The selectivity of CO2 over N2 and CH4 was 87–91% and 83–87%, respectively. The isosteric heat of adsorption (Qst) for CO2 at 298 and 303 K showed an increase in Qst from 36.8 to 47.6 K kJ mol−1, and this would be responsible for high CO2 adsorption energies and faster kinetics. This study reports first-time imprinting of CO2-philic templates in the polymers to capture small gas molecules at ambient conditions, and the results demonstrated that the polymers have a wide scope for real-life applications of CO2 capture.

The Chemical Structure of Carbon Nanothreads Analyzed by Advanced Solid-State NMR.

Carbon nanothreads are a new type of one-dimensional sp3-carbon nanomaterial formed by slow compression and decompression of benzene. We report characterization of the chemical structure of 13C-enriched nanothreads by advanced quantitative, selective, and two-dimensional solid-state nuclear magnetic resonance (NMR) experiments complemented by infrared (IR) spectroscopy. The width of the NMR spectral peaks suggests that the nanothread reaction products are much more organized than amorphous carbon. In addition, there is no evidence from NMR of a second phase such as amorphous mixed sp2/sp3-carbon. Spectral editing reveals that almost all carbon atoms are bonded to one hydrogen atom, unlike in amorphous carbon but as is expected for enumerated nanothread structures. Characterization of the local bonding structure confirms the presence of pure fully saturated "degree-6" carbon nanothreads previously deduced on the basis of crystal packing considerations from diffraction and transmission electron microscopy. These fully saturated threads comprise between 20% and 45% of the sample. Furthermore, 13C-13C spin exchange experiments indicate that the length of the fully saturated regions of the threads exceeds 2.5 nm. Two-dimensional 13C-13C NMR spectra showing bonding between chemically nonequivalent sites rule out enumerated single-site thread structures such as polytwistane or tube (3,0) but are consistent with multisite degree-6 nanothreads. Approximately a third of the carbon is in "degree-4" nanothreads with isolated double bonds. The presence of doubly unsaturated degree-2 benzene polymers can be ruled out on the basis of 13C-13C NMR with spin exchange rateconstants tuned by rotational resonance and 1H decoupling. A small fraction of the sample consists of aromatic rings within the threads that link sections with mostly saturated bonding. NMR provides the detailed bonding information necessary to refine solid-state organic synthesis techniques to produce pure degree-6 or degree-4 carbon nanothreads.

Electronic Structure Characterization of Cross-Linked Sulfur Polymers.

Cross-linked polymers of elemental sulfur are of potential interest for electronic applications as they enable facile thin-film processing of an abundant and inexpensive starting material. Here, we characterize the electronic structure of a cross-linked sulfur/diisopropenyl benzene (DIB) polymer by a combination of soft and hard X-ray photoelectron spectroscopy (SOXPES and HAXPES). Two different approaches for enhancing the conductivity of the polymer are compared: the addition of selenium in the polymer synthesis and the addition of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) during film preparation. For the former, we observe the incorporation of Se into the polymer structure resulting in a changed valence-band structure. For the latter, a Fermi level shift in agreement with p-type doping of the polymer is observed and also the formation of a surface layer consisting mostly of TFSI anions.

BenzoDODA grafted polymeric resin—Plutonium selective solid sorbent

A new ligand grafted polymeric resin (BenzoDODA SDVB) was synthesized by covalently attaching plutonium selective ligand (BenzoDODA) on to styrene divinyl benzene (SDVB) polymer matrix. BenzoDODA SDVB resin was evaluated for separation and recovery of plutonium(IV) from nitric acid medium. Sorption of Pu(IV) was found to decrease with the increase in nitric acid concentration, with very small sorption above 7.0M HNO3. Sorption kinetics was fast enough to achieve the equilibrium within 60min of contact where the kinetic data fitted well to pseudo-second-order model. Sorption isotherm data fitted well to Langmuir model suggesting chemical interaction between the BenzoDODA moiety and plutonium(IV) ions. Sorption studies with some of representative radionuclides of high level waste showed that BenzoDODA SDVB is selective and therefore could be a promising solid sorbent for separation and recovery of plutonium. Further, the theoretical calculations done on BenzoDODA SDVB resin suggested Pu(NO3)4·BenzoDODA (1:1) sorbed complex conformed to generally observed square antiprism geometry of the plutonium complexes, with contributions from oxygen atoms of four nitrate ions as well as from four oxygen atoms present in BenzoDODA (two phenolic ether oxygen atoms and two carbonyl oxygen atoms of amidic moiety).

PGM market report: outlook for platinum: supply & demand in 2016

A new ligand grafted polymeric resin (BenzoDODA SDVB) was synthesized by covalently attaching plutonium selective ligand (BenzoDODA) on to styrene divinyl benzene (SDVB) polymer matrix. BenzoDODA SDVB resin was evaluated for separation and recovery of plutonium(IV) from nitric acid medium. Sorption of Pu(IV) was found to decrease with the increase in nitric acid concentration, with very small sorption above 7.0 M HNO3. Sorption kinetics was fast enough to achieve the equilibrium within 60 min of contact where the kinetic data fitted well to pseudo-second-order model. Sorption isotherm data fitted well to Langmuir model suggesting chemical interaction between the BenzoDODA moiety and plutonium(IV) ions. Sorption studies with some of representative radionuclides of high level waste showed that BenzoDODA SDVB is selective and therefore could be a promising solid sorbent for separation and recovery of plutonium. Further, the theoretical calculations done on BenzoDODA SDVB resin suggested Pu(NO3)4·BenzoDODA (1:1) sorbed complex conformed to generally observed square antiprism geometry of the plutonium complexes, with contributions from oxygen atoms of four nitrate ions as well as from four oxygen atoms present in BenzoDODA (two phenolic ether oxygen atoms and two carbonyl oxygen atoms of amidic moiety).