The analysis of gas evolving during the pyrolysis of two very different rank coals was studied by using FT-IR spectroscopy. These coals, coming from Sulcis (Sardinia, Italy) and from South Africa, respectively, were subjected to progressive heating up to 800°C in vacuum. The thermal destruction of coal was followed by monitoring the production of gases in this range of temperature. The gases evolving in the heating from room temperature to 800°C were collected at intervals of 100°C and analysed by infrared spectroscopy. The relative pressures were plotted against temperature. These graphs clearly show the correlation among qualitative gas composition, temperature, and the maximum value of emissions, thus confirming FT-IR analysis as a powerful key for pyrolysis monitoring. 1. Introduction Pyrolysis represents the first step in most solid fuel conversion processes, including combustion, gasification, and liquefaction, and has a significant influence 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. The unburnt mineral matter can also be released into the air as particulate. However, what concerns the most is CO2 emissions, which are believed to influence climate change. Due to the role that coal plays in the energy production, it would be worthwhile to reduce the negative effects of air pollution caused by and emissions by increasing the efficiency of coal conversion [2–4]. Coal pyrolysis is considered an effective 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 fibres, fine 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 extracted for the production of washing oil, cementitious agent and catalytically hydrogenated products to obtain gasoline, diesel oil, and so forth. Therefore, it is necessary to deepen the
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