The paper represents the research results for the process of crude oil-contaminated soil neutralization with the use of a neutralizer obtained on the basis ofhumic substances. Using physical methods (gas and liquid chromatography, fluorimetry, atomic absorption spectrometry, IR spectrometry), the element and group compositionswere determined for the crude oil-contaminated soil, neutralizer, and neutralized soil. Optimal parameters were determined for the process of the crude oil-contaminated soil neutralization under laboratory conditions:weight ratios of the crude oil-contaminated soil, neutralizer and water, and the temperature and neutralization process duration. The technological scheme was developed for the neutralization of the crude oil-contaminated soil in field conditions. It was found that low-boiling point hydrocarbon fractions (C₁₂–C₁₇) disappear completely at neutralization, the content of high-boiling point hydrocarbon fractions (C₂₀–C₂₃) is essentially increased, and the content of oil components and metals, including the toxic ones, is decreased. The engineering characteristics for nine mixtures of the stabilized soil, containing the neutralized soil, were evaluated under laboratory conditions and the conditions were determined for their use in road construction (with regard to road category, characteristic pavement layer, minimal air temperature). An experimental road section was constructed with the use of the stabilized soil with neutralized soil (40%).

Efficiency of an amine modified Na-Humate (Na-Hum), which was isolated from coal mine in Karaganda/Kazakhstan, was explored as a sorbent for removal of toxic metal ions from water. Na-Hum was immobilized with ethylene diamine to get a suitable adsorbent called modified humate (Mod-Hum). Pseudo-first-order and pseudo-second-order kinetic models gave the best correlation at the suitable pH. The experimental results were calculated according to the related adsorption formulas, which were then depicted in tables and graphics. The amount of toxic metal ions remained in the solution after treating with Mod-Hum was measured by atomic absorption spectroscopy. The process parameters such as mixing time, temperature, and pH during the adsorption were investigated to find optimum sorption capacity. The results after adsorption were compared to determine the differences between natural (Na-Hum) and the modified matter (Mod-Hum). The complexation ability of compounds by exchange of Na-Hum and Mod-Hum with several metal ions such as Cu(CH₃COO)₂·H₂O, Co(CH₃COO)₂·4H₂O, Ni(CH₃COO)₂·4H₂O, and Cd(CH₃COO)₂·2H₂O was also investigated. All obtained compounds were characterized by several techniques such as FTIR, TGA/DTA, and SEM-EDAX, elemental analysis and XRD. The adsorption studies with both Na-Hum and Mod-Hum clearly demonstrated that Na-Humate treated with amine is a more efficient adsorbent than the natural form. In addition, Mod-Hum fitted better with pseudo-first-order model and removed water contaminants such as Cu, Co, Ni, and Cd more effectively, which was attributed to higher reactivity of N and O donor sites of the adsorbent toward toxic metals.

This article presents the potential use of a humic agent called ‘Superhumate’, obtained from weathered coal from the Shubarkol deposit in Kazakhstan. The experiment was conducted using model solutions and surface mine water samples from the “Degelen” site at the Semipalatinsk Test Site. The adsorption of heavy metals and toxic elements using the “Superhumate” agent was carried out under dynamic conditions using a chromatographic column. Tests were conducted at a natural pH range of 5–8 (mine waters) and with a model solution at pH 1.7. Assessing the sorption efficiency of this preparation revealed that at pH 1.7, the agent does not adsorb elements such as Cd, Cu, Pb, and Zn. Under dynamic experimental conditions, using the preparation for mine waters at natural pH levels (pH 5–8), elements such as Be, Sr, Mo, Cd, Cs, Zn, and U were efficiently adsorbed at levels of 60–95%. The sorption efficiency of Pb ions was found to be almost independent of pH. The experimental results obtained with mine water samples indicate that alkaline solutions have the highest sorption efficiency, with pH ≥ 7, which is attributed to the solubility of the agent.