Application of response surface methodology for optimization of trace amount of diazinon preconcentration in natural waters and biological samples by carbon mesoporous CMK‐3

Abstract

Preconcentration of trace amounts of diazinon by carbon mesoporous CMK-3 in water and biological samples and measurement by high-performance liquid chromatography were investigated. CMK-3 was prepared using hexagonal SBA-15 as the template. The synthesized materials were characterized by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy, Brunaur-Emmet-Teller, transmission electron microscopy and Boehm titration method. The preconcentration procedure was optimized using a multivariate optimization approach following a two-stage process. The effect of analytical parameters including the amount of the CMK-3 as an adsorbent, pH, type and volume of eluent and flow rate of eluent and sample were studied by a screening project, then the effective parameters were optimized by response surface methodology based on central composite design. The average extraction efficiency of diazinon under optimal conditions (CMK-3 dosage = 25 mg, sample flow rate = 2.5 mL min , eluent flow rate = 1.25 mL min , volume of methanol as an eluent =3.5 mL and initial pH = 6) was 97.11%, which agrees well with the predicted response value (97.93%). The linearity of the method was in the range of 0.5-100 μg L with a correlation coefficient of 0.997. Enrichment factor, limit of detection and limit of quantification were 285.7, 0.09 and 0.23 μg L , respectively. The relative standard deviation (RSD) under optimum conditions was 2.21% (n = 5). The proposed method was applied to determine diazinon in real water and biological samples. Recovery of diazinon from real samples was between 95.80 and 104.94% with an RSD of 0.19-4.65%. Thus, this method is suitable for the preconcentration and determination of diazinon in real water and biological samples.

Sono‐photo‐assisted heterogeneous activation of peroxymonosulfate by Fe/CMK‐3 catalyst for the degradation of bisphenol A, optimization with response surface methodology

“…The stretching bonds at 1,150 and 1,650 cm −1 in all three materials showed C = O stretching vibration and -OH deformation of water, respectively. The observed bond of 570 cm −1 in the Fe/CMK-3 catalyst is related to Fe-O stretch vibration, which explains that iron nanoparticles have been successfully doped onto the CMK-3 (Beirami et al, 2017;Tang et al, 2014).…”

“…CMK-3 is a group of the ordered mesoporous carbons that has been identified since 1999 and has a hexagonal two-dimensional structure which is synthesized by carbonizing the silica mesoporous materials such as uniform pore size SBA-15 (An et al, 2012;Park, Choi, & Ha, 2008). In comparison with other ordered mesoporous carbons, due to its unique properties such as high surface area, large pore volume, excellent synthesis, physical and chemical stability, and electrochemical energy storage, it has been remarkably used (Barzoki, Rahmani, Shahamat, & Beirami 2018;Beirami, Rahimzadeh Barzoki, & Bahramifar, 2017).…”

Photo-Degradation of Phenol Using TiO2/CMK-3 Photo-Catalyst Under Medium Pressure UV Lamp

“…The synthesis of ordered mesoporous silica SBA-15, as the template for the synthesis of CMK-3, was performed based on the previous study (29). The procedure of the SBA-15 synthesis is as follows: after dissolving 2 g P123 in 60 mL of 2M HCl solution, 15 mL deionized water at 40°C and 4.25 g of TEOS were added.…”