Piotr Cyganowski

Piperazine Functionalized Resins for Au(III), Pt(IV), and Pd(II) Sorption

The result of synthesis of anion exchangers bearing piperazine functionalities is presented in this paper. A series of new ion exchange resins was synthesized by modification of VBC/DVB copolymer with 1(2-aminoethyl)piperazine (resin 1P), 1-amino-4-methylpiperazine (resin 2P), and 1-methylpiperazine (resin 3P). Adsorption studies of gold, platinum, and palladium were conducted with batch and dynamic method from multicomponent solutions containing AuCl4−, PtCl62−, and PdCl42− in the concentration range 10 mg/dm3 to 919 mg/dm3. The resins revealed excellent sorption ability towards these metals. The greatest total sorption capacities were determined as 331 mg/g Au for 2P resin, 405 mg/g Pt for 3P resin, and 150 mg/g Pd for 1P resin. The examined 3P resin showed the best total sorption capacity 796 mg/g. Affinity studies were also conducted. The examined resin 1P revealed the greatest affinity to platinum and palladium (lgK 4.5-5) whereas resin 2P revealed the best affinity to gold where lgK were ca. 4.9.

Effect of Microwave Radiation on the Synthesis of Ion Exchange Resins: A Comparative Study

A series of new ion exchange resins was synthesized in a microwave radiation field by modification of chloromethylated styrene/divinylbenzene (S/DVB) and vinylbenzylchloride/divinylbenzene (VBC/DVB) copolymers using amines. The modification processes have been executed simultaneously using the microwave-assisted method and the most efficient, conventional one. The greatest total sorption capacities for noble metals were achieved for two resins conventionally modified using ETDA ion exchange resins based on S/DVB matrices. The microwave-modified resins reveal only slightly lower and in some circumstances even better sorption capacity for noble metals than their conventionally-modified equivalents. The differences are discussed by effect of the synthesis method as evaluated using FTIR spectrophotometry.

New hybrid matrices for the synthesis of ion-exchange resins. The impact of the synthesis procedure on their porosity, functionalization and sorption of noble metals

ABSTRACT In the search for new polymeric supports for the synthesis of ion-exchange resins, a new method has been assessed. A series of core-shell-type polymeric supports, based on the Amberlite XAD-4 adsorbent and vinylbenzyl chloride-divinylbenzene copolymer, has been obtained. The polymers, characterized by a diversified porous structure, were assessed by their functionalization into anion exchangers and their ability to remove Au(III), Pt(IV) and Pd(II). The efficiency of functionalization using ethylenediamine, as well as sorption capacity, was compared to the textural parameters of the initial supports, defining methods and techniques that will allow materials characterized by the most efficient usage of the vinylbenzyl chloride (VBC) monomer to be obtained.

A method of thermal and chemical activation of waste bleaching earth for preparation of a low-cost carbon-mineral adsorbent for chromium(VI) removal

ABSTRACT In this study, the use of a spent bleaching earth for removal of Cr(VI) ions from aqueous solutions was investigated. The waste material derived from the process of vegetable oil purification was subjected to thermal and chemical activation. The so-prepared carbon-mineral adsorbents were characterised by the uptake of chromium(VI) from synthetic solutions. The highest adsorption capacities were obtained for adsorbents carbonised at 400°C (15.9 mg∙g−1) and activated with H2SO4 (15.8 mg∙g−1). Based on the equilibrium and kinetic studies, it was concluded that the adsorption mechanism was based on chemisorption only since no correlation with the porous texture was found.

Polymerization-Driven Immobilization of dc-APGD Synthesized Gold Nanoparticles into a Quaternary Ammonium-Based Hydrogel Resulting in a Polymeric Nanocomposite with Heat-Transfer Applications

A new method for the production of nanocomposites, composed of gold nanoparticles (AuNPs) and (vinylbenzyl)trimethylammonium chloride-co-N,N-methylene bisacrylamide (VBTAC-co-MBA) hydrogel, is described. Raw-AuNPs of defined optical and granulometric properties were synthesized using direct current atmospheric pressure glow discharge (dc-APGD) generated in contact with a solution of HAuCl4. Different approaches to the polymerization-driven synthesis of Au/VBTAC-co-MBA nanocomposites were tested. It was established that homogenous dispersion of AuNPs in this new nanomaterial with was achieved in the presence of NaOH in the reaction mixture. The new nanocomposite was found to have excellent heat-transfer properties.

Experimental review of microwave-assisted methods for synthesis of functional resins for sorption of rhenium(VII)

ABSTRACT The microwave-assisted syntheses of anion exchange resins were carried out in the presence of selected organic solvents and amines, applying variable radiation density. The polymers were used for sorption of ReO4–, after which, the collected results were set together with the applied synthesis parameters. The greatest Re(VII) sorption capacity of 470 mg Re g−1 was revealed by a resin obtained within 10 min in the presence of N,N-dimethylformamide and 2-methylimidazole at power of 160 W. The outcome of the present research constitutes a set of guides allowing to enhance the resource-efficiency of the process.

Fine polymer imprinted layers for the monitoring of bisphenol A in aqueous solutions

ABSTRACT The present work proposes the use of molecularly imprinted polymer layers (MIPLs) on dehydrochlorinated poly(vinyl chloride) (DHPVC) particles, which could serve as new materials for the separation of bisphenol A (BPA). The best material with MIPLs was obtained using a mixture of methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDMA) with the molar ratio of 4:6 in n-octane as the solvent and with 7 wt.% of BPA, which were grafted onto DHPVC particles. The synthesized materials were investigated for their possible application in the monitoring of BPA contamination in real samples received after the treatment of can of some popular beverages.

pH-responsive molecularly imprinted polymer for sorption and rapid desorption of dibutyl phthalate

ABSTRACT The pH-responsive molecularly imprinted polymers (SR-MIPs) for the removal of dibutyl phthalate (DBP) were obtained. The polymers were synthesized using methyl methacrylate, methacrylic acid, divinylbenzene, and a template mixed at different ratios allowing to optimize the process. The so-prepared SR-MIPs were evaluated at various pH values in processes of DBP sorption. The studies covered evaluation of uptake capacity, sorption kinetics, selectivity, and elution. The imprinted samples are characterized by improved factors comparing to their non-imprinted analogues, revealing also pH-sensitivity. The highest removal of DBP (130 mg g−1) was achieved at pH = 6, while pH-driven desorption (90%) was the most efficient at pH = 8.

Atmospheric Pressure Plasma-Mediated Synthesis of Platinum Nanoparticles Stabilized by Poly(vinylpyrrolidone) with Application in Heat Management Systems for Internal Combustion Chambers

Poly(vinylpyrrolidone)-stabilized Pt nanoparticles (PVP-PtNPs) were produced in a continuous-flow reaction-discharge system by application of direct current atmospheric pressure glow discharge (dc-APGD) operated between the surface of a flowing liquid anode (FLA) and a pin-type tungsten cathode. Synthesized PVP-PtNPs exhibited absorption across the entire UV/Vis region. The morphology and elemental composition of PVP-PtNPs were determined with transmission electron microscopy (TEM) and energy dispersive X-ray scattering (EDX), respectively. As assessed by TEM, PVP-PtNPs were approximately spherical in shape, with an average size of 2.9 ± 0.6 nm. EDX proved the presence of Pt, C, and O. Dynamic light scattering (DLS) and attenuated total reflectance Fourier transform-infrared spectroscopy (ATR FT-IR) confirmed PtNPs functionalization with PVP. As determined by DLS, the average size of PtNPs stabilized by PVP was 111.4 ± 22.6 nm. A fluid containing resultant PVP-PtNPs was used as a heat conductive layer for a spiral radiator managing heat generated by a simulated internal combustion chamber. As compared to water, the use of PVP-PtNPs enhanced efficiency of the system, increasing the rate of heat transfer by 80% and 30% during heating and cooling, respectively.

Antibacterial Activity of Fructose-Stabilized Silver Nanoparticles Produced by Direct Current Atmospheric Pressure Glow Discharge towards Quarantine Pests

Development of efficient plant protection methods against bacterial phytopathogens subjected to compulsory control procedures under international legislation is of the highest concern having in mind expensiveness of enforced quarantine measures and threat of the infection spread in disease-free regions. In this study, fructose-stabilized silver nanoparticles (FRU-AgNPs) were produced using direct current atmospheric pressure glow discharge (dc-APGD) generated between the surface of a flowing liquid anode (FLA) solution and a pin-type tungsten cathode in a continuous flow reaction-discharge system. Resultant spherical and stable in time FRU-AgNPs exhibited average sizes of 14.9 ± 7.9 nm and 15.7 ± 2.0 nm, as assessed by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. Energy dispersive X-ray spectroscopy (EDX) analysis revealed that the obtained nanomaterial was composed of Ag while selected area electron diffraction (SAED) indicated that FRU-AgNPs had the face-centered cubic crystalline structure. The fabricated FRU-AgNPs show antibacterial properties against Erwinia amylovora, Clavibacter michiganensis, Ralstonia solanacearum, Xanthomonas campestris pv. campestris and Dickeya solani strains with minimal inhibitory concentrations (MICs) of 1.64 to 13.1 mg L−1 and minimal bactericidal concentrations (MBCs) from 3.29 to 26.3 mg L−1. Application of FRU-AgNPs might increase the repertoire of available control procedures against most devastating phytopathogens and as a result successfully limit their agricultural impact.