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•Copper undergoes homogeneous ion-exchange binding to both MTS9301 and C107E.•Iron(II) extraction was the lowest of all measured and modelled extraction values.•Lead displays the most ...heterogeneous binding with respect to C107E with low binding energies.•C107E was ineffective for the extraction of zinc from within acetate media.
A large predicted increase in population growth and dwindling phosphate resources has led to sewage sludge being an attractive alternative to commercial fertilisers. Among other contaminants, heavy metals are a barrier to unrestricted use of sewage sludge or sewage sludge ash as a phosphate source. This study will focus on the equilibrium isotherm behaviours of Cu2+, Fe2+, Pb2+ and Zn2+ towards C107E, MTS9301 and TP214 resins within acetic acid media, fit to the two parameter Freundlich, Langmuir, Temkin and Dubinin-Radushkevich (D-R) isotherm models. C107E and MTS9301 were both found to have comparable monolayer capacities for Cu2+ and Fe2+ (5 ± 1 vs 4.3 ± 0.7 mmol·g−1 and 2.1 ± 0.8 vs 2.3 ± 0.8 mmol·g−1 for Cu2+ and Fe2+, respectively). The Freundlich model implied heterogeneous binding for Pb2+ and Zn2+ adsorption to C107E and MTS9301. The monolayer capacities of MTS9301 for lead and zinc were calculated as 2.1 ± 0.2 mmol·g−1 and 3 ± 1 mmol·g−1, respectively. MTS9301 returned larger D-R free energy values than C107E, with the largest difference being Zn2+, displaying energies of 14.0 and 5.5 kJ·mol−1, respectively. TP214 displayed the lowest capacity for metals with Fe2+, Pb2+ and Zn2+ returning D-R energy values closer to physisorption mechanisms (6.0 ± 0.5, 7.1 ± 0.4 and 7.8 ± 0.5 kJ·mol−1, respectively), with copper returning a D-R energy relating to chemisorption (17 ± 1 kJ·mol−1). Overall, it was observed that the similarity of the C107E functionality to the free acetate anion led to the highest level of hindrance, seconded by the interaction between Fe2+, Pb2+ and Zn2+ to TP214, while copper displayed strong interaction with TP214 and MTS9301 displayed little or no hindrance by the acetate complexes in solution, with solution phase complexes affecting the homogeneity of binding within any ion exchange reaction.
Insertion of Peripherally Inserted Central Catheters (PICCs) is potentially associated with the risk of immediate/early adverse events, some of them minimal (repeated punctures) and some relevant ...(accidental arterial puncture or nerve-related injury). Several strategies adopted during the insertion process may minimize the risk of such events, including late complication risks such as infection, venous thrombosis, or catheter dislodgment and/or malposition. This paper describes an update version of the SIP protocol (Safe Insertion of PICCs), an insertion bundle which includes eight effective strategies that aims to minimize immediate, early, or late insertion-associated complications. These strategies include: preprocedural ultrasound assessment utilizing the RaPeVA (Rapid Peripheral Venous Assessment) protocol; appropriate skin antiseptic technique; choice of appropriate vein, adoption of the Zone Insertion Method™; clear identification of the median nerve and brachial artery; ultrasound-guided puncture; ultrasound-guided tip navigation; intra-procedural assessment of tip location; correct securement of the catheter, and appropriate protection of the exit site. This updated version of the SIP protocol includes several novelties based on the most recent evidence-based scientific literature on PICC insertion, such as the clinical relevance of the tunneling technique, the use of ultrasound for intra-procedural tip navigation and tip location, and the new technologies for the protection of the exit site (cyanoacrylate glue) and for the securement of the catheter (subcutaneous anchorage).
A shortage of phosphate rock resources has led to a focus on the use of sewage sludge as a fertiliser. One factor preventing the unlimited application of sewage sludge in agriculture is the heavy ...metal content. This work looks at a process where weak acid leaching of sewage sludge would be coupled to ion exchange (IX) for heavy metal ion removal. IX offers an effective method for the recovery of these metals from a leachate. This study presents the pH performance of six selected IX resins in extracting Cu2+, Fe2+, Pb2+ and Zn2+ from acetic, lactic and citric acid media simulated weak acid leachate. Acetic acid media displayed limited suppression of metal extraction, whilst lactic and citric acid media rendered MTS9100 ineffective. Lactic acid media when combined with C107E resin allows for the targeted extraction of lead. Both MTS9570 and MTS9501 display high ferrous extraction in all media at all pH values, although citric acid hinders extraction by both resins at higher pH values. TP214 is selective for copper over all other metal ions in all weak acid media. MTS9301 is the most effective at extracting all metals from all media solutions, with separation of copper becoming more apparent when transitioning to citric acid.
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•MTS9301 is effective at extracting selected metal ions from all tested media.•Citrate media is effective at hindrance of metal adsorption.•TP214 can selectively extract copper from high complexing solutions.•C107E can selectively extract lead from lactate media.
We report here the carbon dioxide sorption properties for a series of conjugated microporous polymer (CMP) networks. These CMP materials incorporate a range of chemical functionalities including ...carboxylic acids, amines, hydroxyl groups, and methyl groups. The carboxylic acid functionalised network, rather than its amine analogue, shows the highest isosteric heat of sorption for CO2. This supports recent computational predictions for metal-organic frameworks and suggests that acid-functionalised frameworks could outperform more widely studied amine sorbents in CO2 capture and separation application.
Sulfonated hyper-cross-linked polymers based on 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCMBP) were synthesized via metal-free (SHCP-1) and conventional Lewis acid-catalyzed (SHCP-2) Friedel–Crafts ...alkylation routes. The sulfonated polymers possessed BET surface areas in excess of 500 m2·g–1. SHCP-1 was investigated for its ability to extract Sr and Cs ions from aqueous solutions via the ion-exchange reaction of the sulfonic acid moiety. Equilibrium uptake data could be accurately modeled by the Dubinin–Radushkevich isotherm, with maximum calculated loading values of 95.6 ± 2.8 mg·g–1 (Sr) and 273 ± 37 mg·g–1 (Cs). Uptake of both target ions was rapid, with pseudo second-order rate constants calculated as 7.71 ± 1.1 (×10–2) for Sr and 0.113 ± 0.014 for Cs. Furthermore, the polymer was found to be highly selective toward the target ions over large excesses of naturally occurring competing metal ions Na, K, Mg, and Ca. We conclude that hyper-cross-linked polymers may offer intrinsic advantages over other adsorbents for the remediation of aqueous Sr and Cs contamination.
The insertion of central venous catheters through the femoral veins is not uncommon and is potentially associated with the risk of immediate puncture-related complications and severe late ...complications as infection and thrombosis. As for other central venous access devices, the use of a standardized protocol of insertion and the correct application of evidence-based strategies are beneficial in reducing the risk of complications. We proposed a standardized protocol (S.I.F.: Safe Insertion of Femorally Inserted Central Catheters) consisting of seven strategies that should be part of vascular cannulation and should be adopted during the insertion of femoral venous catheters, aiming to minimize immediate, early and late insertion-related complications. These strategies include: preprocedural evaluation of the patient history and of the veins, appropriate aseptic technique, ultrasound guided puncture and cannulation of the vein, intra-procedural assessment of the tip position, adequate protection of the exit site, proper securement of the catheter, and appropriate coverage of the exit site.
A range of conjugated microporous polymer networks has been prepared using Sonogashira−Hagihara cross-coupling of 1,3,5-triethynylbenzene with a number of functionalized dibromobenzenes. Porous ...poly(arylene ethynylene) networks with surface areas up to 900 m2/g were produced. The surface chemistry of the networks was varied by monomer selection, thus allowing control over physical properties such as hydrophobicity. Additionally, it was shown that the dye sorption behavior of the networks can be controlled by varying the hydrophobicity. This expands significantly on the utility of this approach, allowing high surface area networks to be prepared with properties that can be tailored for applications such as catalysis and separations.
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