DEVELOPMENT OF A TECHNOLOGY FOR PRODUCING SOLVENTS FROM A LIQUID BY-PRODUCT

ABSTRACT

This study investigates the composition and utilization potential of a liquid by-product formed during the production of liquefied synthetic fuel as a feedstock for solvent production. The research was carried out using gas chromatography–mass spectrometry (GC–MS) and gas chromatography with flame ionization detection (GC–FID). The analytical results indicate that the liquid by-product is predominantly composed of low-molecular-weight alcohols and oxygen-containing organic compounds. The obtained composition demonstrates that the studied by-product is a promising raw material for the production of industrial solvents with potential applications in chemical and petrochemical processes.

АННОТАЦИЯ

В настоящем исследовании изучены состав и потенциал использования жидкого побочного продукта, образующегося в процессе производства сжиженного синтетического топлива, в качестве сырья для получения растворителей. Исследования проводились с применением методов газовой хроматографии–масс-спектрометрии (ГХ–МС) и газовой хроматографии с пламенно-ионизационным детектором (ГХ–ПИД). Результаты анализа показали, что жидкий побочный продукт преимущественно состоит из низкомолекулярных спиртов и кислородсодержащих органических соединений. Полученный состав свидетельствует о перспективности использования исследуемого побочного продукта в качестве сырья для производства промышленных растворителей, применимых в химических и нефтехимических процессах.

Keywords: synthetic fuel, by-product liquid, solvents, GC–MS, alcohols, distillation.

Ключевые слова: синтетическое топливо, жидкий побочный продукт, растворители, ГХ–МС, спирты, дистилляция.

Introduction

The rapid development of synthetic fuel technologies has intensified the need for integrated utilization of all process streams. During the production of liquefied synthetic fuels, in addition to the main product, various secondary liquid streams are generated, which are often underutilized or treated as low-value fractions. Disposal or inefficient use of such by-products leads to material losses and reduces the overall economic efficiency of the production process.

The aim of this study is to evaluate the composition of a liquid by-product formed during synthetic fuel production and to develop a feasible technological approach for its utilization as an industrial solvent feedstock.

Oxygen-containing organic compounds, particularly low-molecular-weight alcohols, are widely used as solvents in chemical synthesis, extraction processes, coatings, cleaning operations, and pharmaceutical industries. Therefore, converting synthetic fuel by-products into solvent materials is both scientifically relevant and economically attractive, contributing to resource efficiency and sustainable industrial development.

Materials and Methods

GC–MS analysis was performed using an Agilent 7890B gas chromatograph coupled with a 5977A mass selective detector. GC–FID measurements were carried out on an Agilent 7890B system equipped with a flame ionization detector.

The object of this study was a liquid by-product obtained from the liquefied synthetic fuel production process. Samples were analyzed using an Agilent gas chromatography–mass spectrometry (GC–MS) system. Identification of individual compounds was carried out by comparing the obtained mass spectra with the NIST17 mass spectral library.

Quantitative analysis of the major components was performed using gas chromatography with flame ionization detection (GC–FID). Chromatographic parameters such as retention times, peak areas, and relative concentrations were determined. In addition, the fractional composition of the sample was evaluated based on its distillation characteristics to assess its suitability for solvent separation processes.

Results

The results of the GC–MS analysis indicate that the liquid by-product formed during the production of liquefied synthetic fuel is predominantly composed of low-molecular-weight oxygenated organic compounds. The majority of detected components are concentrated at low retention times, confirming the alcohol-rich nature of the investigated liquid by-product. (see Fig. 1)

Figure 1. GC–MS total ion chromatogram of the liquid by-product formed during liquefied synthetic fuel production.

 The vertical axis represents total ion current (TIC, arbitrary units), while the horizontal axis corresponds to retention time in minutes. Values such as 2.57 denote retention times (min) of individual components (e.g., 1‑propanol).

The chromatographic profile demonstrates that the most intense peaks correspond to ethanol, ethyl formate, 1-propanol, and 1-butanol. GC–MS analysis revealed that ethanol is the dominant component, accounting for approximately 45–46% of the total composition. Significant quantities of ethyl formate (about 24%), 1-propanol (around 16%), and 1-butanol (approximately 5%) were also identified. Minor amounts of isobutanol, methyl-propanol, and trace quantities of higher-molecular-weight oxygenated compounds were detected. Components appearing at higher retention times were present only in trace concentrations and are not expected to significantly influence the solvent properties of the mixture.

Quantitative GC–FID analysis confirmed the predominance of alcohols in the studied sample, indicating that the investigated liquid by-product can be effectively considered an alcohol-based solvent mixture.

Figure 2. Distribution of major alcohol components in the liquid by-product obtained from synthetic fuel production

Figure 2 summarizes the quantitative distribution derived from Fig. 1 chromatographic data and does not represent an independent experiment.

As shown in Figure 2, ethanol represents the largest fraction of the mixture, followed by ethyl formate, 1-propanol, and 1-butanol. The high total alcohol content demonstrates that the investigated by-product is suitable for direct use as an industrial solvent or as a feedstock for further solvent fractionation.

Discussion

The obtained results demonstrate that the investigated liquid by-product can be directly utilized or subjected to minimal purification for the production of industrial solvents. Alcohol mixtures containing ethanol, propanol, and butanol are widely applied in coatings, cleaning operations, extraction processes, and various chemical and petrochemical technologies.

From a technological standpoint, fractional distillation represents an effective method for separating the by-product into individual solvent fractions. The relatively low boiling points of the dominant alcohol components enable separation with moderate energy consumption, thereby improving the overall process efficiency. Moreover, the internal reuse of such solvent fractions within synthetic fuel production facilities may significantly reduce operational costs and enhance process integration.

Conclusion

The study confirms that the liquid by-product formed during the production of liquefied synthetic fuel contains a high proportion of low-molecular-weight alcohols. This composition makes it a promising feedstock for the production of industrial solvents. Utilization of this secondary process stream enables more efficient use of raw materials, reduces waste generation, and contributes to the sustainability and economic performance of synthetic fuel technologies.

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