Process-Oriented Evaluation of Nitrite-Based Extraction and Upgrading of Oil Sands Bitumen: Case Study of the Karasyaz–Taspas Deposit (Kazakhstan)

The growing depletion of conventional crude oil resources has intensified interest in unconventional hydrocarbon feedstocks such as oil sands and natural bitumen. This study presents an integrated recovery and upgrading of oil sands bitumen from the Karasyaz–Taspas deposit: process development and product characterization. Experimental investigations included bitumen extraction, atmospheric and vacuum distillation, and comprehensive physicochemical characterization (density, viscosity, elemental composition, and SARA fractions). The extraction process achieved a recovery efficiency of up to 98%, demonstrating the effectiveness of the applied approach under mild temperature conditions. The obtained results indicate that the bitumen is characterized by a balanced fractional composition with a significant yield of middle distillates and oil fractions, which makes it a promising feedstock for the production of fuels, base oils, and bituminous materials. A process flow scheme integrating extraction, fractionation, and upgrading stages is proposed and discussed from a technological perspective. The study provides a practical assessment of the applicability of nitrite-based extraction systems for oil sands processing and highlights the potential for implementing modular processing units under field conditions. The findings contribute to the development of resource-efficient approaches for the utilization of Kazakhstan’s unconventional hydrocarbon resources.