A new cotton functionalized with iron(III) trimer-like metal framework as an effective strategy for the adsorption of triarylmethane dye: An insight into the dye adsorption processes.

A new Cotton@Fe-BTC composite formed by Fe-BTC (BTC-H3: trimesic acid) metal framework (Fe-BTC MOF loading as high 38 wt %) supported by cellulose fiber is synthesized in aqueous media using a simple and green preparation method, described for the first time in this manuscript. This new strategy relies on the synergetic effect of the pure cellulose and MOFs frameworks resulting in hybrid nanofibers of MOFs@cellulose composite. A complete characterization of the composite material reveals its structural similarity to MIL-100(Fe), a Fe-BTC material. The Cotton@Fe-BTC composite potential use as an eco-friendly and low-cost adsorbent was evaluated for its adsorptive performance for the removal of dye belonging to the triarylmethane dye family (Malachite Green (MQ), Brilliant Green (BG), Pararosaniline (PR), Basic Fuchsine (BF), Crystal Violet (CV), Methyl Green (Met-G), Victoria Blue B (VB), Acid Fuchsin (AF) and Aniline Blue (AB)) in aqueous solution. The fast kinetics and high dye removal efficiencies (>90%) obtained in aqueous solutions. The structure of Cotton@Fe-BTC network, contributed to the remarkable adsorption properties towards a variety of triphenylmethanedye. The interparticle studies showed two main steps in the dye adsorption processes, with the exception of AF and BG. The equilibrium adsorption capacities qe (mg/g) follow the order: AF (3.64)

Metal organic framework composite, nano-Fe3O4@Fe-(benzene-1,3,5-tricarboxylic acid), for solid phase extraction of blood lipid regulators from water.

The magnetic metal-organic framework Fe3O4@(Fe-(benzene-1,3,5-tricarboxylic acid) (MMOF) was prepared, characterized and studied as a magnetic sorbent for the dispersive solid-phase extraction (DSPE) of several widely used blood lipid regulators (i.e., bezafibrate, clofibric acid, clofibrate, gemfibrozil and fenofibrate) from water samples. Characterization of the synthesized Fe3O4@Fe-BTC magnetic nanomaterial was performed by Fourier transform infrared spectroscopy, powder X-ray diffractometry, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The magnetic nanocomposite was found to be chemically stable and to possess a large surface area (803.62 m2/g) and pore volume (0.59 cm³/g). The concentrations of fibrates in different water samples were determined using HPLC-UV-Vis and confirmed by UPLC-MS/MS. Parameters affecting the extraction efficiency of magnetic-DSPE were studied and optimized. The maxima absorption capacities (Qmax) were determined to be (in mg/g) 197.0 for bezafibrate, 620.3 for clofibric acid, 537.6 for clofibrate, 288.7 gemfibrozil and 223.2 for fenofibrate. Validations of the optimized magnetic DSPE method for analyses at two fibrate concentrations in spiked water samples produced relative recovery values ≤ 70% for clofibrate and within the range of 80-100% for bezafibrate, clofibric acid, gemfibrozil and fenofibrate. LODs ranging from 4 µg/L for fenofibrate to 99 µg/L for gemfibrozil were obtained. The validated methodology produced recovery values ranging from 70 to 112% (relative standard deviations < 7%).

Adsorption of silver nanoparticles from aqueous solution on copper-based metal organic frameworks (HKUST-1).

Silver nanoparticles (AgNP) are emerging pollutants. The use of novel materials such as Cu-(benzene 1,3,5-tricarboxylate, BTC) Metal-Organic Framework (MOFs), for AgNP adsorption and their removal from aqueous solutions has been studied. The effect of different parameters was followed and isotherm model was suggested. MOFs adsorbed fast and efficiently AgNP in the range C0 < 10 mg L(-1), being Freundlich isotherm (R = 0.993) these data fitted to. Among studied parameters a remarkable effect of chloride on sorption was found, thus their possible interactions were considered. The high adsorption efficiency of AgNP was achieved and it was found to be very fast. The feasibility of adsorption on Cu-(BTC) was proved in spiked waters. The results showed the potential interest of new material as adsorbent for removing AgNP from environment.

Validation of a GC-MS/MS method for simultaneous determination of 86 persistent organic pollutants in marine sediments by pressurized liquid extraction followed by stir bar sorptive extraction.

A multiresidue method for the analysis of 86 persistent pollutants in marine sediments at ultra-trace level has been developed and validated using pressurized liquid extraction (PLE) and stir-bar sorptive extraction (SBSE) coupled with thermal desorption and gas chromatography-triple quadrupole mass spectrometry (TD-GC-MS/MS QqQ). The compounds analyzed belong to various families such as polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polybrominated diphenylethers, organophosphorus and organochlorine pesticides and other pesticides such as urons, and triazines. The analytes have very different polarities and log K(ow) values, which is an important parameter in the optimization of a SBSE method. Due to PLE high efficiency and throughput rates, along with the proven ability for multiresidue analysis and excellent sensitivity of SBSE, we present an efficient method. The limits of quantification obtained ranged from 0.014 to 1.0 ng g(-1), with detection limits below pg g(-1) levels. In order to validate the proposed methodology, quality parameters such as recovery, linearity and reproducibility were studied. Recoveries ranged from 63% to 119%, reproducibility (in terms of Relative Standard Deviation for ten determinations) was lower than 35% in all cases, and determination coefficients higher than 0.990 for all analytes. The main factors that affect PLE, SBSE and GC-MS/MS procedures were optimized. The method was applied to the analysis of nine marine sediments obtained from the nine main submarine wastewater discharge points (emissaries) presents along the coast of Tenerife Island (Canary Islands, Spain).