Highly efficient and simultaneous removal of 2‐mercaptobenzothiazole and 2‐mercaptobenzoxazole from water samples by copper oxide nanoparticles

Abstract

BACKGROUND: This study introduces a method for simultaneous removal of 2-mercaptobenzoxazole (2MBO) and 2mercaptobenzothiazole (2MBT) from water samples. The method uses a cartridge loaded with copper oxide nanoparticles as an efficient adsorbent to separate these hazardous mercaptans from aqueous solutions in a flow process. RESULTS:The effects of some important parameters such as amounts of adsorbent, pH, buffer type and its volume, electrolyte concentration, contact time, flow rate, tolerable volume of solution, reusability of cartridges and interfering ions on removal efficiency were studied. Data on adsorption were analyzed using linear and non-linear forms of first-and second-order kinetic equations and also Langmuir and Freundlich isotherm models and results showed that maximum adsorption amounts of 90.9 mg g −1 and 158.7 mg g −1 , were obtained for 2MBO and 2MBT, respectively. CONCLUSION: The proposed removal method is independent of pH level of the sample solution and is effective over a wide range of pH values. Using a copper oxide nanoparticle loaded cartridge (CONLC) has the advantage that there is no need to collect nanoparticles after the removal process and that CONLC can be reused for further removal processes (at least three times). This method was successfully applied to remove 2MBT (≥95% removal) from the cooling water of a 3000 MW power plant.

Determination of benzomercaptans in environmental complex samples by combining zeolitic imidazolate framework-8-based solid-phase extraction and high-performance liquid chromatography with UV detection

“…Finally, the developed material was compared with other extraction sorbents of target analytes in environmental samples (see Table 4). Regarding aqueous samples analysis, the recovery values obtained were quite similar to those found in most reported studies; however, in certain works [23,28] these values were lower than 65%. Regarding the LODs, our values were better than those described by Parham et al [24], and similar to those reported in refs.…”

“…Other advantage found is the less amount (20 mg) of sorbent required compared with single-use commercial SPE sorbents (commonly up to 150-500 mg) [28,30,31]. This amount was also similar to a nanomaterial-based method using CuNPs [23,24] probably due to surface area-to-volume ratio; however, its reusability was quite lower than that found in the present study.…”

“…Among organic pollutants, benzomercaptans, such as 2-mercaptobenzothiazole (MBT) and 2-mercaptobenzoxazole (MBO), deserve special attention due to their broad use in many industrial processes. These compounds are commonly used as vulcanization accelerators in the rubber industry, as biocorrosion inhibitors, as coating agents of metallic surfaces, and as biocides in medical applications [23][24]. As consequence, such compounds have been found in different environmental compartments such as surface waters, wastewater effluents, sewage treatment plants, soils, roadsides, etc.…”

“…In order to reach these low concentrations, determination techniques mainly based on LC combined with mass spectrometry detectors have been reported [28][29][30][31]. In any case, sample preparation techniques are required in order to reduce matrix interferences and to improve sensitivity to benzomercaptans in environmental complex samples, being SPE the most common technique used for extraction and preconcentration of these kind of analytes [23,24,28,30,31]. However, SPE shows some disadvantages, such as limited selectivity and poor reusability.…”

Photodegradation of odorous 2-mercaptobenzoxazole through zinc oxide/hydroxyapatite nanocomposite

“…Some studies on the environmental behavior and the biodegradation of MBO indicated that in environmental conditions it is very stable and cannot completely mineralized (Allaouia and Wong-WahChung 2010; Habibi and Sheibani 2012). To the best of our knowledge, very few works were reported specifically on the removal of MBO (Antonopoulou et al 2014;Habibi and Sheibani 2010;Parham and Khoshnam 2013). Hence, in aspect of established toxicity, low biodegradability and persistence of MBO in natural compartments, further work on its elimination and/or mineralization needs to be addressed.…”