The Pre-concentration and determination of Iridium and Palladium in environmental water by imprinted polymer-based method

Abstract

In this study, the imprinted aniline-formaldehyde was used as an adsorbent for removal of Iridium and Palladium ions from aqueous solutions through batch equilibrium. The sorbent was characterized by fourier transform infrared spectroscopy. The influence of pH, equilibrium time, temperature and initial concentration of metal ions on adsorbed amount of both ions were investigated. The maximum adsorption capacity in initial concentration of 100 mg/L was found to be 12.5 mg/g at pH 7.0 and 14.3 mg/g at pH 8.0 for Iridium and Palladium, respectively. In addition, the best desorption of the metal ions from resin was obtained by 0.5 mol/L nitric acid as eluting agent. The profile of both ions uptake on this sorbent reflects good accessibility of the chelating sites in the imprinted aniline-formaldehyde. Langmuir, Freundlich, Temkin and Redlich-Peterson isotherm models were applied to analyze the experimental data. Moreover, Langmuir linear method was used to obtain the isotherm parameters. However, Langmuir type II achieved the highest coefficient which led to the best fit for the palladium and the best fit for Iridium obtained from linear Redlich-Peterson. However, the thermodynamic parameters (DG°, DH°, and DS°) were also determined using the equilibrium constant values obtained at different temperatures. The results showed that the adsorption for Iridium and Palladium ions was spontaneous nature and endothermic. Moreover, the method was applied for the determination of both ions from tap water samples.

Radical scavenging capacity, antibacterial activity, and quantum chemical aspects of the spectrophotometrically investigated iridium (III) complex with benzopyran derivative

“…Thus, there is an increasing demand for the development of analytical procedures, preferably simple, sensitive, and selective ones to broaden the horizon of the applicability of iridium and its complexes. Sophisticated techniques such as NAA (Miura et al, 2020), spectrofluorimetric (Druskovic et al, 2004), AAS (Ingo et al, 2008), voltammetry (Locatelli, 2013), atomic emission and flame emission spectrometry (Jackson and Qiao, 1992), ICP-OES (Zhang and Tian, 2015), ICP-MS (Yi and Masuda, 1996), sequential flow injection analysis (Khomutova et al, 2013), imprinted polymerbased method (Sid Kalal et al, 2013), and individual catalytic method (Kawamura et al, 2011) have been employed for the purpose. However, the wider application of these techniques is restricted by several factors such as instrumentation costs, technical know-how, and maintenance issues.…”

Current status and challenges of ion imprinting

“…Sr-IIPs have been synthesized by surface imprinting with palygorskite as a sacricial support. 117 The monolayer adsorption capacity of Sr-IIPs is 45.0 mg g À1 at 298 K, 53.5 mg g À1 at 308 K and 58.5 mg g À1 at 318 K. Kalal et al 118 have synthesized Sr-IIPs based on aniline-formaldehyde for extraction of Sr by SPE from tap water samples. Hrdina et al 119 synthesized crown ether modied cation exchange IIP particles, attaining 86 AE 2% 90 Sr uptake at pH ¼ 9 when applied in urinalysis.…”

Spectrophotometric determination of iridium after complexation and membrane filtration

“…Therefore, highly selective, sensitive, rapid and economical methods are needed for its trace and ultra trace determination. Neutron activation analysis (NAA) [11], atomic absorption spectrometer (AAS) [12], graphite furnace AAS [13], individual catalytic [14], imprinted polymer-based [15], sequential voltammetric [16] and flow injection analysis [17] may be used for the trace determination of iridium in complex materials, however, these instruments are highly expensive, day to day maintenance is high and not free from various types of interferences [18][19][20]. A survey of the literature reveals that iridium may be determined by zero order spectrophotometry using phenanthrenequinone monoxime [21] (e = 2.3 Â 10 4 L mol À1 cm À1 ) perazine dimalonate [22] (e = 9.93 Â l0 3 L mol À1 cm À1 ), tetrahydrofurfuryl xanthate [23] (e = 5.02 Â l0 3 L mol À1 cm À1 ), 1-phenyl-4,4-6-trimethyl-(1H,4H)-pyrimidine-2-thiol [24].…”