A Liquid Membrane Mercury Selective Electrode Based on 2-(N-pipyridino Methyl)-1-Cyano Cyclohexanol as a Novel Neutral C
- PDF / 595,764 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 48 Downloads / 175 Views
RTICLES
A Liquid Membrane Mercury Selective Electrode Based on 2-(NPipyridino Methyl)-1-Cyano Cyclohexanol as a Novel Neutral Carrier Hamid Reza Rashvanda, Leila Hajiaghababaeia ,b, *, Mohammad Raouf Darvicha, Mohammad Reza Jalali Sarvestanib, and Firouz Jaberi Miyandoaba aDepartment
of Chemistry, Yadegar-e-Imam Khomeini (RAH) Shahre-rey Branch, Islamic Azad University, Tehran, Iran Young Researchers and Elite Club, Yadegar-e-Imam Khomeini (RAH) Shahre-rey Branch, Islamic Azad University, Tehran, Iran *e-mail: [email protected]
b
Received April 21, 2018; revised August 12, 2018; accepted April 29, 2020
Abstract—2-(N-pipyridino methyl)-1-cyano cyclohexanol was synthesized, characterized and used as an ionophore in construction of polyvinyl chloride (PVC) potentiometric sensor for Hg2+ determination. The best result was obtained with membrane composition of PVC (29%), sodium tetraphenylborate as ionic additive (1%), 2-(N-pipyridino methyl)-1-cyano cyclohexanol (12%) and dibutylphthalate (58%). The designed electrode showed an acceptable Nernstian slope (29.1 mV/decade) for Hg2+ over a wide concentration range from 5 × 10–7 to 1 × 10–2 M with a detection limit of 2.5 × 10–7 M. The potential response was independent from pH in the range of 6.0–9.0 and the sensor response time was relatively short (~25 s). The sensor performance was invariable for at least 6 weeks. Electrode selectivity was evaluated by matched potential method. Finally, the proposed sensor was used as an indicator electrode in potentiometric titration of Hg2+ with ethylenediaminetetraacetic acid and in direct determination of mercury(II) in aqueous samples with admissible accuracy and high reproducibility. Keywords: mercury selective electrode, liquid membrane, 2-(N-pipyridino methyl)-1-cyano cyclohexanol, potentiometry DOI: 10.1134/S106193482010010X
Mercury is a silvery-white liquid heavy metal that is known as the 80th element of the periodic table with Hg symbol and its most common oxidation state is +2. This perilous element occurs in three forms in nature (metallic, organic and inorganic) which originate from both natural sources such as volcanic eruptions and geothermal phenomena as well as human activities including mining, burning garbage and excessive use of fossil fuels [1, 2]. Mercury can have more toxic and destructive effects than other heavy metals such as lead and cadmium, due to its high volatility and long life time in atmosphere, so that, the United States Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) classified mercury and its related compounds as the third most poisonous chemicals in Priority List of Hazardous Substances [3]. Even trace amounts of this toxic metal can cause numerous diseases such as Alzheimer, autism, insomnia, anxiety, attention deficit, hyperactivity disorder, hearing loss, autoimmune disorders, respiratory diseases and depression [4–8]. Moreover, in higher doses, it can lead to mercurialism (mercury poisoning) that can be diagnosed by such symptoms as agita-
tion, ata
Data Loading...
