11268 - Analytical Chemistry of Pollutants

Learning outcomes

The aim of the course is to provide the student with the basic knowledge of the most common analytical techniques for the analysis of inorganic ions, natural substances, metabolites, and toxicants in environmental matrices. In particular, the student will be able to understand the information provided by the most common analytical techniques and define a correct procedure for chemical analyses and reporting of results.

Course contents

Module 1: Room lectures

- Instrumental analysis, calibration, and validation (6 hours). Instrumental analysis and calibration curves, construction of a calibration curve, linear and non-linear calibration curves, linearization of calibration curves, principles of regression analysis, linear and non-linear regression, determination coefficient, error on interpolated values, evaluation of the quality of a calibration curve, calibration methods (external calibration, internal calibration, calibration with standard addition), validation of an analytical method, standard reference materials, characteristics of an analytical method (accuracy, precision, specificity and selectivity, linearity, dynamic interval, LOD, LOQ, robustness), control samples, laboratory quality control, control charts.

- Instrumental analytical techniques (9 hours): Spectroscopic analytical methods: atomic and molecular spectra, absorption spectra of organic compounds and transition metal complexes, quantitative analysis (Lambert-Beer law), molecular absorption spectroscopy, instrumental configurations, molecular emission spectroscopy, spectrofluorimeters, quantitative analysis, turbidimetry and nephelometry, atomic spectroscopy, atomization and atomizers (flame, electrothermal and plasma), absorption, emission and mass spectrometry detection techniques. Potentiometry: potentiometric techniques, indicator and reference electrodes, ion-selective membrane electrodes, glass pH electrode, gas probes. Chromatography: chromatographic techniques, theory of chromatography (chromatograms, retention time, resolution, efficiency, number of theoretical plates, band broadening), qualitative and quantitative analysis, gas chromatography – GC (carrier gas, injection system, columns, detectors, gas-liquid and gas-solid chromatography, programmed temperature separation), high performance liquid chromatography – HPLC (mobile phase, pumps, injection system, columns, detectors, types of liquid chromatography, elution gradient separation).

- Analysis of pollutants (14 hours). Basics and characteristics of the main classes of pollutants: production, transport, distribution, bioaccumulation, sampling, and sample storage procedures. Water quality parameters and measurement techniques: dissolved and suspended solids, dissolved oxygen, BOD, COD, pH, conductivity, hardness, common inorganic ions. Volatile organic pollutants: sample treatment (static and dynamic headspace extraction, solid phase microextraction), gas chromatographic analysis. Semivolatile and nonvolatile organic pollutants: sample treatment (liquid-liquid extraction, solid phase extraction, solid phase microextraction, solid-liquid extraction, microwave-assisted extraction, accelerated solvent extraction, supercritical fluid extraction), HPLC analysis, immunoassays. Metals: sample treatment (liquid-liquid extraction, solid phase extraction, gaseous hydride extraction, calcination, humid digestion, microwave-assisted digestion, speciation analysis), atomic spectroscopy, spectrophotometry, electrochemical techniques. Atmospheric pollutants: sampling techniques for atmospheric pollutants (active and passive sorbent systems, gas detector tubes, particulate and wet/dry deposition sampling systems), portable analyzers, monitoring and long-range detection systems, direct chemical analysis of particulate.

Practical exercise

- Construction and use of calibration curves (3 hours). Basics on Microsoft Excel, use of Excel for data processing, data graphing, drawing and linearization of calibration curves.

Module 2: Laboratory exercises

As concerns the teaching methods of this course unit, all students must attend Module 1, 2 [https://www.unibo.it/en/services-and-opportunities/health-and-assistance/health-and-safety/online-course-on-health-and-safety-in-study-and-internship-areas] online, while Module 3 on health and safety is to be attended in class. Information about Module 3 attendance schedule is available on the website of your degree programme

- Spectrophotometric determination of nitrites.

- Spectrophotometric determination of iorn ion.

- Turbidimetric determination of sulphates.

- Potentiometric determination of the ammonium ion.

- Immunometric determination of progesterone.

- Determination of endocrine modulators by solid phase extraction and high-performance liquid chromatography (HPLC).

Readings/Bibliography

- PowerPoint slides of room lectures, material for the exercise on the construction of calibration curves, instructions for laboratory exercises and for drafting laboratory reports available on “Insegnamenti online” (http://iol.unibo.it/, access with credentials reserved for students enrolled at the University of Bologna).

- Fondamenti di Chimica Analitica di Skoog e West - J.F. Holler, S.R. Crouch - 3° Ed. (EdiSES, 2015).

- Chimica Analitica Quantitativa - D.C Harris - 3° Ed. (Zanichelli, 2017).

- Chimica Ambientale - C. Baird, M. Cann - 3° Ed (Zanichelli, 2013).

- Introduction to Environmental Analysis - R.N. Reeve - 1° Ed. (Wiley, 2002).

- Methods for Environmental Trace Analysis - J.N. Dean - 1° Ed. (Wiley, 2003).

Teaching methods

The course is made up of 6 credits (Module 1: 4 credits room lectures, Module 2: 2 credits laboratory exercises). During the lectures the topics of the course will be presented and discussed, with theoretical insights and explanatory examples. The single-seat laboratory exercises are designed to allow each student to acquire the knowledge of some instrumental analytical techniques used in environmental analysis and the necessary skills for working in a laboratory according to quality and safety guidelines. Laboratory exercises include the analysis of unknown samples. The student will process the results obtained in the laboratory using the tools learned in the course and will submit reports with the analysis of the data and the concentration of his unknown sample.

Assessment methods

Verification of knowledge on the whole program by means of the following tests.

- Oral exam on the topics covered during the course, aimed at verifying the acquisition of knowledge and expected skills. In particular, the knowledge of calibration procedures employed in instrumental analytical chemistry, the understanding of the basic principles and procedures of the main instrumental analytical techniques for environmental analysis, the knowledge of the sampling, treatment and analysis procedures regarding the measurement of pollutants in the most common environmental matrices (air, water, soil) will be evaluated. Evaluation will be based on the demonstration of the critical understanding of the topics and the ability to discuss them.

- Evaluation of the laboratory exercises conducted based on the reports submitted by the student. For such evaluation, both the correctness of the procedures used for the elaboration of the experimental data and the concordance of the obtained results with the real concentrations of the unknown samples will be considered.

The final grade will consist of the sum of the marks obtained in the oral exam (maximum 20/30) and in the laboratory exercises (maximum 10/30). The submission of the reports according to the modalities that will be agreed during the laboratory is mandatory to be admitted to the final exam.

Teaching tools

Video projector, computer room, analytical laboratory equipped with the necessary instrumentation for performing single-seat instrumental analysis. The teaching material (PowerPoint presentations, material for the exercise on the construction of calibration curves, instructions for laboratory exercises and for drafting laboratory reports) will be made available to the student in electronic format on “Insegnamenti online” (http://iol.unibo.it/, access with credentials reserved for students enrolled at the University of Bologna). Such material should be printed and brought to class and/or laboratory.

Office hours

See the website of Donato Calabria