Water Analysis

Abstract

This review covers developments in Water Analysis over the period of 1999-2000. A few significant references that appeared between January and February 2001 are also included. Previous Water Analysis reviews have been very comprehensive, often including more than 500 references. This year, however, Analytical Chemistry is changing its approach to these reviews to only include 100-200 significant references and to mainly focus on trends in analytical methods. This was a difficult task, as the scope of Water Analysis is inherently broad, encompassing analytical studies involving all types of contaminantssorganic and inorganic, as well as microorganisms. Rather than choosing a subarea to focus on, this review will still attempt to cover most areas, except with fewer references. As a result, this review was by necessity very selective, and not all good references could be discussed. Typically, when there were two or more of the same type of analytical method developed for a particular set of analytes, only one was chosen as representative of the method. Also, in this review, there is more of a focus on the analytical methods themselves and less on results from significant studies. Papers focusing on the treatment of pollutants are generally omitted, as are most health effects papers. The upside to including fewer references is that those included can be discussed in greater detail, and more attention can be given to trends and comparisons of new methods to former ones.Numerous abstracts were consulted before choosing the best ones to present here. If an abstract was generally unclear or ambiguous, it was generally excluded. If the subject matter of the abstract appeared to be of routine nature, with no new, significant findings, it was also generally excluded. A table of acronyms is included (Table 1) as a quick reference to the acronyms of analytical techniques and other terms discussed in this review.The overall trends in analytical methods for water analysis include a greater use of solid-phase microextraction (SPME); fast gas chromatography (GC), and liquid chromatography (LC) methods; more on-line coupling of separation and extraction with detection (such as ion chromatography (IC) coupled to inductively coupled plasma mass spectrometry (ICPMS), IC coupled to atmospheric pressure chemical ionization mass spectrometry (APCI-MS), solid-phase extraction (SPE) coupled to LC/MS or GC/MS, and membrane introduction mass spectrometry (MIMS) coupled to fast-GC/MS; and increased use of capillary electrophoresis (CE), large-volume GC injection, and enzyme-linked

Kinetic Determination of Mercury(II) at Trace Level from Its Catalytic Effect on a Ligand Substitution Process

“…In the presence of traces of mercury(II), the substitution rate increased and this change in rate was measured absorptometrically. Figure 1 shows the absorption spectra of reactants and product [ Fe ( CN ) 5 Mpz ] 2-. It was found that the reaction proceeds at normal temperature in an acidic medium.…”

“…It was found that the reaction proceeds at normal temperature in an acidic medium. The substituted product [ Fe ( CN ) 5 Mpz ] 2-absorbs strongly at 655 nm without any interference from the reactants Hg 2+ , K 4 [ Fe ( CN ) 6 ] and Mpz + , while the absorbance depends on the concentrations of the reactants, the pH, the temperature, and the ionic strength. The effect of these variables was therefore studied to optimize the reaction by monitoring the change of absorbance at 655 nm { λ max of [ Fe ( CN ) 5 Mpz ] 2-, ε = (1.25 ± 0.01) × 10 4 mol L -1 cm -1 [31]}.…”

“…The substituted product [ Fe ( CN ) 5 Mpz ] 2-absorbs strongly at 655 nm without any interference from the reactants Hg 2+ , K 4 [ Fe ( CN ) 6 ] and Mpz + , while the absorbance depends on the concentrations of the reactants, the pH, the temperature, and the ionic strength. The effect of these variables was therefore studied to optimize the reaction by monitoring the change of absorbance at 655 nm { λ max of [ Fe ( CN ) 5 Mpz ] 2-, ε = (1.25 ± 0.01) × 10 4 mol L -1 cm -1 [31]}. Fixed time plots were utilized to find the reaction rate's dependence on pH and [Hg 2+ ], while initial rate (V i ) plots were used to find the dependence of rate on [Mpz + ], [Fe(CN) 6 ] 4-, temperature and ionic strength.…”

“…Being toxic, it should be regularly monitored in a wide variety of samples such as air, water, soil, food, and human blood and urine. During the past decade, many new and improved methods for determination of mercury(II) have been developed and are listed in earlier reviews [1][2][3][4][5][6]. Many of these, however, lack sufficient sensitivity for determining mercury at subnanogram per milliliter levels.…”

Adsorption studies for the simultaneous removal of arsenic and selenium using naturally prepared adsorbent materials

“…Trace metal contamination of most water sources has intensified the effect of the scarcity of safe/potable water for human consumption (Richardson 2001;Richardson and Ternes 2011;Chen and An 2012;Kamsonlian et al 2012;Igwe et al 2008). Arsenic and selenium have been identified as two of the most toxic trace metals and are found in most aqueous environments with deficiencies closely associated with toxic levels (Peak 2006;Jain and Ali 2000;Hamilton 2004).…”