Petrochemical enterprises in Kazakhstan discharge polluted wastewater into special recipients. Contaminants infiltrate through the soil into the groundwater, which potentially affects public health and environment safety. This paper presents the evaluation of a 7-year monitoring program from one of the factories and includes nineteen variables from nine wells during 2013–2019. Several multivariate statistical techniques were used to analyse the data: Pearson’s correlation matrix, principal component analysis and cluster analysis. The analysis made it possible to specify the contribution of each contaminant to the overall pollution and to identify the most polluted sites. The results also show that concentrations of pollutants in groundwater exceeded both the World Health Organization and Kazakhstani standards for drinking water. For example, average exceedance for total petroleum hydrocarbons was 4 times, for total dissolved solids—5 times, for chlorides—9 times, for sodium—6 times, and total hardness was more than 6 times. It is concluded that host geology and effluents from the petrochemical industrial cluster influence the groundwater quality. Heckman two-step regression analysis was applied to assess the bias of completed analysis for each pollutant, especially to determine a contribution of toxic pollutants into total contamination. The study confirms a high loading of anthropogenic contamination to groundwater from the petrochemical industry coupled with natural geochemical processes.

The present article is an assessment of wastewater treatment processes in the oil refinery sector in Kazakhstan by comparing relevant experience of developed and developing countries. The legislation in this sphere, the treatment methods, the discharge process and the effect on the environment were evaluated following international and national regulations. In our study, the wastewater systems in three factories in Kazakhstan were assessed. Results show that, even though the environmental regulation in Kazakhstan promotes the polluter pays principle and follows the World Health Organization (WHO) recommendations, the oil refinery plants in Kazakhstan still contain exceeding concentrations of pollutants in their effluents. One issue is that the local legislation allows disposal of wastewater to natural or artificial ponds as long as the concentrations of pollutants in effluents are less than the already existing concentrations in the pond. Consequently, the factories can use ponds with an initially high concentration of contaminants. The high initial concentration of pollutants in the pond water is due to wastewater discharged before the implementation of current environmental regulations. This issue in the current legislation leads to the situation where there is no incentive for efficient wastewater treatment. The national law also lacks regulations regarding which methodology should be used to assess the pollutants in the wastewater. Thus, the control by national environmental office for each enterprise is negotiated separately between the factory and the governmental body. This gives the factory a strong position to define the parameters assessing the effluents. This has led to none of the factories measuring, e.g., heavy metals in discharged wastewater. Total petroleum hydrocarbons (TPH) concentration in wastewater is often exceeded at each factory and there is no analysis done for different hydrocarbon fraction. To overcome the issues described in the present study, we strongly recommended a unified and transparent methodology for the country’s oil refinery industry to assess important pollutants in discharged wastewater.

The investigation of the course of the Boudouard reaction and methane cracking was performed over nickel catalysts based on oxides of calcium, aluminum, and magnesium. The catalytic samples were synthesized by the impregnation method. The physicochemical characteristics of the catalysts were determined using atomic adsorption spectroscopy (AAS), Brunauer–Emmett–Teller method analysis (BET), temperature-programmed desorption of ammonia and carbon dioxide (NH₃- and CO₂-TPD), and temperature-programmed reduction (TPR). Qualitative and quantitative identification of formed carbon deposits after the processes were carried out using total organic carbon analysis (TOC), temperature-programmed oxidation (TPO), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The selected temperatures for the Boudouard reaction and methane cracking (450 and 700 °C, respectively) were found to be optimal for the successful formation of graphite-like carbon species over these catalysts. It was revealed that the activity of catalytic systems during each reaction is directly related to the number of weakly interacted nickel particles with catalyst support. Results of the given research provide insight into the mechanism of carbon deposit formation and the role of the catalyst support in this process, as well as the mechanism of the Boudouard reaction.

One of the most promising ways to utilize wastes from the oil extracting and oil refining industries, in particular oil sludge, is their processing into valuable construction and road materials. Solving this issue can help reduce the negative impact on the environment, rational use of natural resources and improve the state’s economy. In this regard, it is important to conduct research on the physical and chemical properties and thermal characteristics of oil sludge samples taken at oil refineries of the Republic of Kazakhstan, as well as the possibility of using them as an additive for bitumen grade BND 70/100.

The valorization of industrial solid wastes into construction materials represents an important pathway toward resource efficiency and carbon reduction in the building sector. In this study, sustainable kaolinitic clay-based ceramics were developed using ternary blends of steel slag (SS), coal fly ash (CFA), and recycled waste glass bottle-derived powder (WGBP). The effects of WGBP content and firing temperature on phase evolution, microstructural development, densification behavior, and key physico-mechanical properties were systematically investigated. The results show that at intermediate temperatures (1000–1100 °C), the addition of 5 wt% WGBP promotes liquid-phase sintering, leading to enhanced densification, reduced water absorption, and compressive strengths up to 44 MPa, whereas higher glass contents at elevated temperature induce over-fluxing and pore entrapment, reducing strength despite comparable density. XRD, FTIR, and SEM analyses confirm the progressive vitrification and structural reorganization of the aluminosilicate matrix. The sustainability assessment identifies the 5 wt% WGBP formulation as the most balanced option, combining adequate mechanical performance with lower energy demand and CO₂ emissions. Overall, the proposed approach provides a technically viable and resource-efficient route for the integrated utilization of multiple industrial wastes in construction ceramics.