GC-MS ANALYSIS OF ORGANIC COMPOUNDS IN COAL GASIFICATION PROCESS

ABSTRACT

This study investigates the coal gasification process and industrial waste utilization for combustible gas production. The chemical composition of raw materials was analyzed using gas chromatography-mass spectrometry (GC-MS). The results identified key organic compounds, including hydrocarbons, oxygen- and nitrogen-containing compounds, as well as polycyclic aromatic hydrocarbons (PAHs). Docosane (C₂₂H₄₆) was found to be a crucial component of liquid fuels due to its high energy efficiency and thermal stability. The gasification method demonstrated a CO₂ emission reduction of up to 35% and an energy production efficiency increase of 40%. The obtained data contribute to optimizing carbon feedstock processing and improving the environmental sustainability of energy production.

АННОТАЦИЯ

В данной работе исследуется процесс газификации угля и промышленных отходов с целью получения горючих газов. Проведен анализ химического состава исходного сырья с использованием метода газовой хроматографии-масс-спектрометрии (GC-MS). В результате исследования выявлены основные органические соединения, включая углеводороды, кислородсодержащие и азотсодержащие соединения, а также полициклические ароматические углеводороды (ПАУ). Установлено, что докозан (C₂₂H₄₆) является ключевым компонентом жидкого топлива, поскольку обладает высокой энергетической эффективностью и термической стабильностью. Метод газификации продемонстрировал снижение выбросов CO₂ до 35% и увеличение КПД производства энергии на 40%. Полученные результаты позволяют оптимизировать процессы переработки углеродного сырья и повысить экологическую безопасность энергопроизводства.

Keywords: coal gasification, GC-MS analysis, hydrocarbons, docosane, polycyclic aromatic hydrocarbons, energy efficiency, liquid fuel.

Ключевые слова: газификация угля, GC-MS анализ, углеводороды, докозан, полициклические ароматические углеводороды, энергетическая эффективность, жидкое топливо.

INTRODUCTION

Coal is one of the most important energy sources globally, accounting for approximately 37% of the world's electricity [1]. However, its direct combustion releases large amounts of harmful substances into the atmosphere, including CO₂, SOx, and NOx, which exacerbates global warming and environmental problems [2]. Therefore, there is a need to introduce more efficient and environmentally friendly technologies than traditional combustion methods. Coal gasification technology is considered a solution to this problem, as it has high efficiency, reduces waste volume, and reduces environmental risks [3]. In addition, gasification not only produces energy, but also provides hydrogen, synthetic gas, and chemical raw materials, which further increases the strategic importance of this process [4].

This study aims to assess how the physicochemical composition of raw materials affects gasification efficiency. Key tasks include analyzing the impact of ash, CO₂, sulfur, and other coal components, comparing technological methods to determine optimal conditions, and examining gas composition ratios (CH₄, H₂, CO). Additionally, the study evaluates environmental efficiency, waste composition, and recycling options. Finally, criteria will be established to identify the most efficient coal types for high-quality gas production, ensuring better resource utilization.

Figure 1. Efficiency and environmental impact of coal gasification methods

Coal gasification technology is characterized by high efficiency and environmental safety compared to traditional combustion methods. Research results show that because of this process, energy production efficiency can increase by up to 40% [5]. In addition, this technology allows the processing of low-quality coal and waste materials, paving the way for more efficient use of natural resources [6].

Coal gasification is carried out using various technological methods, including dry gasification (pyrolysis), steam-oxygen gasification, air gasification, plasma gasification and underground gasification (UCG). Pyrolysis is carried out at temperatures of 400-700°C and produces solid residue and gas [7], while steam -oxygen gasification produces a gas with a high content of hydrogen and carbon monoxide at temperatures of 1000-1500°C [8]. Air gasification involves the participation of atmospheric air, which results in a low flammability of the resulting gas [9], while plasma gasification allows the production of pure gas at temperatures above 2000°C but requires a large amount of energy [10].

MATERIALS AND METHODS

Coal gasification technology has become an important technology in modern energy systems and is based on the production of fuel gases through the gasification process. This process is carried out because of partial combustion of coal in the presence of air and water vapor. The gasification system consists of several main components, of which the air compressor serves to supply compressed air, and the water tank serves to direct water vapor to the furnace. The furnace (reactor) is the main part of the gasification process, in which fuel gases are formed under the influence of coal and catalysts. Coal, catalyst, and oil sludge are placed in sections 4–7, and the reducer reduces the pressure and controls the gas flow. The resulting gas is discharged through a valve, stored in a gas holder, and then used as fuel by a burner (combustion chamber) and a flame. The air reducer and air valve control and regulate the amount of air supplied to the system.

The scientific basis of the gasification process is based on the interaction of coal with air and water vapor, which occurs at high temperatures (700–1200°C). They are used to speed up this process, increasing the efficiency of gas production. The resulting gas contains CH₄ (methane), H₂ (hydrogen), CO (carbon monoxide), and CO₂ (carbon dioxide), the proportions of which vary depending on the gasification conditions.

Figure 2. Technological scheme of fuel production based on coal and factory waste. 1- air compressor, water tank, 3- furnace, 4, 5, 6, 7 - coal hopper, 8- reducer, 9 - tap for extracted gas, 10- gas golder, 11- burner, 12- flame, 13- air reducer, 14- air tap

To increase the efficiency of the technology, the air and steam supply were optimized. Because if there is not enough air or steam, the reaction will not occur completely, and the gas composition will decrease. Therefore, it is recommended to install automated sensors that operate in real time. In addition, catalysts such as nickel (Ni), iron (Fe) and ruthenium (Ru) were used to improve the gas composition, as they accelerate the decomposition process of hydrocarbons.

Waste gas purification is one of the important scientific problems, as the gas may contain sulfur compounds (H₂S) and other harmful components. To reduce these emissions, it is necessary to introduce special adsorption filtration systems. Filter systems reduce environmental risks by removing sulfur and other harmful elements. It is also necessary to improve the gas storage system, ensuring long-term storage of gas using high-pressure gas holders.

To increase energy efficiency, it is advisable to introduce a heat exchange system. The heat from the exhaust gas can be recycled and returned to the system, which increases overall energy efficiency. This approach can increase the efficiency of the energy production process by 15–20%. Therefore, in-depth study of the scientific foundations of coal gasification technology and improvement of technological systems are important factors in the formation of a sustainable energy strategy for the future.

To increase productivity, studies were conducted on the gasification process based on coal samples and waste from the Ustyurt gas and chemical plant and the Shurtan gas and chemical complex. This approach not only improves energy production efficiency, but also helps solve environmental problems by reducing industrial waste. The research included a thorough analysis of the composition of each raw material and the study of the impact of their chemical properties on the gasification process.

RESULTS AND DISCUSSION

The composition of the waste from the Ustyurt gas and chemical plant was analyzed using the GC-MS (gas chromatography-mass spectrometry) method. According to the results of the study, hydrocarbon compounds, oxygen- and nitrogen-containing organic substances, as well as traces of some heavy metals were detected in the waste.

Figure 3. Ustyurt gas - chemistry factory waste sample f -32 's GC - MS (gas chromatography - mass spectrometry) image

The analysis results are presented in the form of a gas chromatogram, and each peak (emission time) is determined to be associated with specific chemical compounds. The main components and their distribution according to the retention time (RT) are presented below:

Table 2.

Results of GC-MS analysis of the composition of the Ustyurt gas and chemical plant effluent

The results of GC-MS analysis of the waste from the Ustyurt gas and chemical plant show that the composition of the oil sludge mainly consists of alkanes, aromatic hydrocarbons and high molecular weight resin components, and the presence of polycyclic aromatic hydrocarbons (PAH) is an environmentally hazardous factor. Many compounds in the PAH composition have toxic and carcinogenic properties, and thermal degradation methods can be used to reduce their environmental impact. During pyrolysis (450–800°C), PAH decomposes into short-chain hydrocarbons, significantly reducing the number of harmful substances. Gasification (900–1200°C) converts PAH into carbonyl gases and hydrogen in an oxygen-free environment, increasing their energy efficiency and ensuring environmental safety.

The compound bi-2,4-cyclopentadien-1-yl, 1,1',2,2',3,3',4,4',5,5'-decachloro-(C₁₀Cl₁₀) is characterized by its highly chlorinated structure and has a molecular weight of 356 g/mol, identified by the CAS number 2227-17-0 (Figure 4). Mass spectrometry (MS) analysis allowed us to determine the decomposition characteristics of this compound, with the main peaks observed at m/z values 237, 242, 262, 332, 404 and 474. The fragments at m/z 237 and m/z 242 are formed because of the loss of Cl atoms, reflecting the decomposition mechanism of the molecule. The peak at 332 m/z corresponds to a fragment that retains many chlorine atoms, indicating its thermal and chemical stability. The values at 404 m/z and 474 m/z are high molecular mass fragments, indicating that the compound may undergo complex degradation processes.

Figure 4. Mass spectrometry (MS) image of 1,1',2,2',3,3',4,4',5,5'-decachloro-(C₁₀Cl₁₀)

The combination of gas chromatography (GC) and mass spectrometry (MS) provides high accuracy and sensitivity in determining the composition of substances in a sample. The GC method separates each component into fractions based on the volatility of the components, while MS determines the molecular mass of the separated components and performs their chemical identification.

Figure 5. Mass spectrometry (MS) image of 3-Bromopyridine

The results of mass spectrometry (MS) analysis show that the obtained spectrum corresponds to the compound 3-Bromopyridine (C₅H₄BrN). The strongest peak characteristic of this substance is 157 m/z, which corresponds to the molecular ion mass and reflects the stability of the compound (Figure 5). The 78 m/z fragment in the spectrum is formed because of the cleavage of the pyridine ring and characterizes the characteristics of the decomposition process. The results of this analysis serve as an important scientific basis in organic synthesis processes, in the analysis of fuel components, and in chemical research.

Table 3.

Gas Chromatography Results: Retention Time (RT) and Chemical Composition

GC - MS analysis results this shows that in the sample various to factions belonging hydrocarbon compounds, as well as oxygen and nitrogen keeper organic substances available. Light hydrocarbons (RT = 3.69–5.12 min) are alkanes and alkenes with low boiling points, which can be used as fuels and solvents. Middle fractions (RT = 9.55–12.10 min) contain diesel and kerosene components, and their energy efficiency and stability during combustion are of great importance for industry. Esters and phenols have been identified in the composition of oxygen- and nitrogen-containing organic substances (RT = 13.29–15.40 min), which have potential use in the pharmaceutical, cosmetic, and paint industries. Heavy fractions (RT = 16.36–18.48 min) may contain polycyclic aromatic hydrocarbons (PAH), and such compounds have toxic and carcinogenic properties, which require improved environmental monitoring and waste treatment systems. The analysis results allowed the identification of compounds such as 1,3-Cyclopentadiene, 1,2,3,4,5,5-hexachloro-(C₅Cl₆) and Pyridine, 3-bromo-(C₅H₄BrN), which are important for the fuel industry, which expands the energy efficiency of hydrocarbons and their conversion into liquid fuels.

Figure 6. Ustyurt gas - chemistry factory waste sample f - 39 's GC - MS (gas chromatography - mass spectrometry) image

According to the analysis results, light hydrocarbons (C₅–C₁₀ alkanes and alkenes) were detected in the sample in the RT range of 3.70–5.16 min, with the main peak recorded at 4.79 min. Heavy fractions, including aromatic and polycyclic hydrocarbons (PAH), were detected in the RT range of 16.30–18.48 min, with significant peaks recorded at 16.30, 17.61, and 18.01 min.

Figure 7. Mass spectrometry (MS) spectrum of docosane (Docosane, C₂₂H₄₆)

According to the analysis results, the main components in the sample and their release times (RT) were distributed as follows:

Table 4.

Gas Chromatography Results: Retention Time (RT) and Chemical Composition

GC-MS analysis confirms the presence of various organic compounds in the sample, which are significant for both industry and environmental considerations. Light hydrocarbons (RT = 3.70–5.99 min), including alkanes and alkenes, are widely used in fuels, solvents, and petroleum products, while middle fractions (RT = 7.13–11.21 min) contain diesel- and kerosene-like hydrocarbons with high energy efficiency and low carbon emissions. Heavy fractions (RT = 16.30–18.01 min) contain polycyclic aromatic hydrocarbons (PAH), requiring strict monitoring due to their potential toxicity, emphasizing the need for improved waste treatment and environmental safety measures.

Table 5.

Advantages of Docosane compared to other substances

GC-MS analysis identifies Docosane (C₂₂H₄₆) as a key hydrocarbon in the fuel industry due to its high energy efficiency and role in stabilizing liquid fuel composition. It is directly usable as fuel, produced from coal-derived synthesis gas via Fischer-Tropsch synthesis, and widely applied in diesel and aviation fuels for its superior thermal stability and flammability.

CONCLUSION

Coal gasification and industrial waste processing enhance energy efficiency while reducing environmental impact, increasing energy production by up to 40% and cutting CO₂ emissions by 35%. GC-MS analysis confirms the presence of hydrocarbons and oxygen- and nitrogen-containing compounds in Ustyurt gas-chemical plant waste, indicating their recycling potential, with Docosane (C₂₂H₄₆) identified as a highly efficient fuel component. Steam-oxygen and plasma gasification methods demonstrated the highest efficiency, while catalysts like nickel (Ni), iron (Fe), and ruthenium (Ru) are recommended to optimize gas composition.

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