Hindawi Publishing Corporation Journal of Combustion Volume 2013, Article ID 134234, 14 pages http://dx.doi.org/10.1155/2013/134234 Research Article FT-IR Investigation of the Structural Changes of Sulcis and South Africa Coals under Progressive Heating in Vacuum: Correlation with Volatile Matter Aldo D’Alessio, Anna Maria Raspolli-Galletti, Domenico Licursi, and Marco Martinelli Dipartimento di Chimica e Chimica Industriale, Universit` a di Pisa, Via Risorgimento 35, 56126 Pisa, Italy Correspondence should be addressed to Aldo D’Alessio; aldo@dcci.unipi.it Received 30 January 2013; Revised 27 May 2013; Accepted 31 May 2013 Academic Editor: Peter F. Nelson Copyright © 2013 Aldo D’Alessio et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. he analysis of gas evolving during the pyrolysis of two very diferent rank coals was studied by using FT-IR spectroscopy. hese coals, coming from Sulcis (Sardinia, Italy) and from South Africa, respectively, were subjected to progressive heating up to 800 ∘ C in vacuum. he thermal destruction of coal was followed by monitoring the production of gases in this range of temperature. he gases evolving in the heating from room temperature to 800 ∘ C were collected at intervals of 100 ∘ C and analysed by infrared spectroscopy. he relative pressures  () = () / max() () were plotted against temperature. hese graphs clearly show the correlation among qualitative gas composition, temperature, and the maximum value of emissions, thus conirming FT-IR analysis as a powerful key for pyrolysis monitoring. 1. Introduction Pyrolysis represents the irst step in most solid fuel conversion processes, including combustion, gasiication, and liquefac- tion, and has a signiicant inluence on every subsequent stage for the recovery of valuable chemicals and energy [1]. Coal has been used for a long period both as fossil fuel and as raw material by the chemical industry. Currently, petroleum and natural gas represent the two main energy sources, but it is well-known that these supplies have no longer kept pace with the ever-increasing energy demand of many nations. As a result, an imperative need to rely on a well-known energy source such as coal is paramount. Unfortunately, impurities of coal such as sulphur and nitrogen derivatives are released into the atmosphere causing problems such as acid rains and smog. he unburnt mineral matter can also be released into the air as particulate. However, what concerns the most is CO 2 emissions, which are believed to inluence climate change. Due to the role that coal plays in the energy production, it would be worthwhile to reduce the negative efects of air pollution caused by CO  and NO  emissions by increasing the eiciency of coal conversion [2–4]. Coal pyrolysis is considered an efective way for its clean use because desulfurized char and tar can be obtained at the end of the reaction. Coal tar can be utilized as raw material for the industrial synthesis of dyes, plastics, synthetic ibres, ine chemicals, and cosmetic products, due to its good activity as a cosmetic biocide [5]. It is also a type of raw material from which phenols, naphthalenes, and anthracene can be extract- ed for the production of washing oil, cementitious agent and catalytically hydrogenated products to obtain gasoline, diesel oil, and so forth. herefore, it is necessary to deepen the un- derstanding of the pyrolysis process, by investigating both raw materials and the originated products, in order to opti- mize the reaction conditions. he study of pyrolysis is also of interest for its possible application to innovative materials such as biomass. Both coal and biomass have complex structures containing a number of diferent constituents. hese constituents show their inherent individual characteristics during thermal processes, and each one contributes to the apparent thermal characteristics of the feedstock. On the other hand, when coal and biomass are treated as blend in processes such as copyrolysis, cocombus- tion, or cogasiication, some positive synergistic interactions