The paper presents the research results on the colorimetric behavior of impregnated fibrous chemisorbents (IFCS-I) of acid gases with visual identification of the dynamic absorption capacity “response” moment during the absorption of sulfur dioxide. Chemisorbents were obtained by impregnation of fibrous carriers by N-containing organic bases aqueous solutions with adding acid-base indicators (Ind). IFCS-I based on hexamethylenetetramine (IFCS-HMTA-I) and polyethylenepolyamine (IFCS-PEPA-I), as well as IFCS-MEA-EDTA-I based on monoethanolamine (MEA) and the disodium salt of ethylenediaminetetraacetic acid (EDTA) were used. The change specificity of colorimetric functions of indicator impregnated fibrous chemisorbents during their absorption of SO2 is revealed. IFCS-I original samples color significantly depends not only on the structure of Ind, but also the nature of amines (MEA, HMTA and PEPA), which are part of them. The color of the “response” samples of IFCS-MEA-EDTA-I, IFCS-PEPA-I and IFCS-HMTA-I, differ from the same properties of Bronsted acids aqueous solutions. The color change of azo-indicators occurs due to redox reactions with sulfite compounds. PEPA molecules and their ammonium cations in the composition of IFCS-I stabilize azo-indicators to these redox transformations.

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The samples of the solid component of welding aerosols (SCWAs) formed in the electric arc plasma in the process of steel welding by electrodes of Ukrainian manufacture (ANO-4, ANO-21, UONI 13/55, and TsL-11,) differed in their chemical composition. The samples were characterized by X-ray phase analysis, IR spectroscopy, and water vapor ad/desorption. The results obtained allow suggesting the influence of a phase composition on the structuraladsorption properties of SCWAs.