Analysis and comparison of kerosene FTIR spectra using the developed cryogenic-capillary system with low-temperature cell

Abstract

This work introduces a technology for FTIR spectroscopy of hydrocarbon materials at low temperatures and atmospheric pressure. This device allows to study optical properties of various substances at temperature range of 77 – 300 K without need of a vacuum and to obtain new fundamental data since there is insufficient research in this area. The purpose is to obtain new fundamental insights into the behavior and properties of hydrocarbon fuels under these conditions, as research utilizing this technology remains relatively uncommon.  This approach allows for the examination of the optical properties of various substances under atmospheric pressure in the temperature range of 77 to 300 K, without the need for a vacuum environment. The study outlines a method for analyzing hydrocarbons using an infrared (IR) Fourier spectrometer, a diffuse reflection attachment, and two Dewar vessels. One vessel is used for cooling samples with liquid nitrogen inside the cryogenic capillary system, while the second creates an IR-inactive environment where the samples are placed. FTIR spectra of the characteristic C-H functional group peaks in kerosene were obtained, reflecting the types and frequencies of their vibrations in specific wavenumber ranges. These findings can be utilized in cryophysics and cryotechnology laboratories worldwide as proof of the feasibility of such research, supporting the development of similar technologies to acquire new fundamental data on the behavior and properties of various substances at atmospheric pressure and low temperatures.