tar

The work is devoted to a completely new binder for asphalt-concrete mixtures, in particular, crushed stone-mastic mixtures. In the role of a binder, it is proposed to use raw materials for the production of bitumen − tars modified with a forming agent (catalyst and formalin). The paper proves the advantage of using tar modified with formalin, in comparison with standard oxidized bitumens, on the example of established physical and mechanical properties of bituminous binders and crushed-mastic asphalt concrete SMA-15.

The study results of the process obtaining of petroleum bitumen with improved quality indicators are described. The method of mixing the tar of paraffinic oils with the residue and the distillation of Orkhiv oil with subsequent oxidation of this mixture was used. To conduct the research, tar extracted from Western Ukrainian paraffinic oils was used. The influence of temperature, oxidation duration and air consumption on the operational properties of oxidized petroleum bitumens were determined.

Three samples of bituminous material with different softening temperatures of 321, 332, and 356.4 K were obtained by the method of chemical modification of tar with formaldehyde using sulfuric acid as a catalyst. The determination of the group hydrocarbon composition was carried out for the raw materials of the modification process (tar) and the resulting bitumens. An FTIR study of the obtained groups of hydrocarbons (oil, resins, and asphaltenes) was also carried out.

The effect of factors on the process of chemical modification of tar with formaldehyde using a sulfuric acid as the catalyst has been studied. By using experimental results, the adequate statistical-mathematical (ESM) model has been developed. Based on this model, the optimal values on the process of chemical modification of tar with formaldehyde using a sulfuric acid as the catalyst have been identified, bringing about optimal penetration value and softening point of the modified tars.

A technology of briquetting of sub-standard coal of Kazakhstan fields to obtain high-quality briquetting fuel has been developed. A modifying additive in the form of oil residues has been selected, that make it possible to obtain a binder composition for brown coal briquetting. The material for the preparation of coal briquettes is coal fines from dry, poorly sintered coals, which cannot be used for direct combustion in the furnace. The optimal parameters for obtaining high-quality fuel briquettes have been determined.

The chemical modification of tar with formaldehyde as 37% aqueous solutionhas been studied in the presence of the catalysts. Hydrochloric acid, sulfuric acid, sodium hydroxide and acid tar were used as the catalysts. The effect of the catalyst nature and amount, as well as temperature, process time and initial components ratio on the softening point, penetration, brittle point and adhesion to crushed stone has been determined. The structure of the modified tars was confirmed by IR spectroscopy. The structural-group composition was determined.

The process of tar and industrial petroleum resin “Piroplast-2” joint oxidation has been investigated. The experimental results of the main regularities researches of the obtaining process of petroleum resins with carboxyl groups based on the pyrocondensate C9 fraction of hydrocarbon feedstock pyrolysis have been shown. It has been established that synthesized petroleum resins may be used for the modification of petroleum bitumens.

Experimental results concerning main regularities of paraffin tar and petroleum resins joint oxidation are presented. It has been shown that petroleum resin in the amount of 5 mas % as raw material component allows to intensify oxidation and improve operational characteristics of obtained bitumen.