Submicron silica spheres decorated with silver nanoparticles as a new effective sorbent for inorganic mercury in surface waters

Abstract

An analytical method using silica supported silver nanoparticles as a novel sorbent for the enrichment and determination of inorganic mercury (iHg) in surface water samples has been developed. Silver nanoparticles (AgNPs) were synthesized by a completely green procedure and were deposited onto the amine functionalized surface of silica submicrospheres (SiO2-NH2). The prepared nanocomposite material (SiO2/AgNPs) was characterized by transmission electron microscopy, UV-vis spectroscopy, X-ray diffraction and atomic force microscopy. The sorption and desorption characteristics of the nanosorbent SiO2/AgNPs toward Hg species were investigated by a batch method. An excellent separation of iHg and methylHg was achieved in 20 minutes at pH 2. The high selectivity of the SiO2/AgNPs toward iHg was explained by Hg(ii) reduction and subsequent silver-mercury amalgam formation. The analytical procedure for the enrichment and determination of inorganic mercury in surface waters was developed based on solid phase extraction and ICP-MS measurements. The total Hg content was determined after water sample mineralization. The recoveries reached for iHg in different surface waters e.g. river and Black sea water samples varied from 96-101%. The limits of quantification are 0.002 μg L(-1) and 0.004 μg L(-1) for iHg and total Hg, respectively; the relative standard deviations varied in the ranges of 5-9% and 6-11% for iHg and total Hg, respectively, for Hg content from 0.005 to 0.2 μg L(-1). The accuracy of the procedure developed for total Hg determination was confirmed by a comparative analysis of surface river (ICP-MS) and sea (CV AFS) waters.

Inorganic engineered nanoparticles in drinking water treatment: a critical review

“…247,262 The remarkable optical properties and high extinction cross-section of Ag nanoparticles allowed them to be used as colorimetric sensors as well as for the removal of toxic ions such as Hg and As species from water. 247,262 The remarkable optical properties and high extinction cross-section of Ag nanoparticles allowed them to be used as colorimetric sensors as well as for the removal of toxic ions such as Hg and As species from water.…”

Application of Metallic Nanoparticles and Their Hybrids as Innovative Sorbents for Separation and Pre-concentration of Trace Elements by Dispersive Micro-Solid Phase Extraction: A Minireview

“…In a multistep process, Yordanova et al ( 2014 ) prepared AgNPs supported on the surface of NH 2 -functionalized silica submicrospheres (SiO 2 /AgNPs) to be used as a sorbent for separation and pre-concentration of inorganic mercury in surface water samples during extraction procedure. This novel nanocomposite adsorbent was synthesized by a completely green procedure and was rigorously characterized by transmission electron microscopy (TEM), UV-Vis spectroscopy, X-ray diffraction (XRD), and atomic force microscopy (AFM).…”

EBT anchored SiO23-D microarray: a simultaneous entrapper of two different metal centers at high and low oxidation states using its highest occupied and lowest unoccupied molecular orbital, respectively

“…So, a selective separation and preconcentration method for sample clean-up to obtain the trace target species in a small volume, prior to its detection/estimation by means of sophisticated instruments, is urgently required. 2,3 In comparison with other techniques [4][5][6][7][8][9][10][11][12][13] with poor recovery and selectivity, [14][15][16] solid-phase extraction (SPE) creates much attention as it possesses many advantages. An appreciable selectivity and high values of preconcentration factors (PF) make SPE as an efficient method for sample cleanup of an analyte.…”

“…These chelating agents act as selective metal trapping centers and normally the selectivity of the material is a function of solution pH. The chemical graing protocols reported so far 3,23,[37][38][39][40][41][42][43][44][45][46][47] are rather complicated (reuxing for more than 24 h, requirement of several toxic/hazardous and costly chemicals such as diethyl ether, pyridine, dichloromethane, chloroacetyl chloride, 2-aminothiophenol, acetonitrile etc. ), 25 time consuming (72-120 h) and sometimes require noble metal catalysts.…”