CCUS (carbon capture, utilization, and storage) technology is regarded as a bottom method to achieve carbon neutrality globally. CO₂ storage in deep coal reservoirs serves as a feasible selection for CCUS, and its storage potential can be attributed to the CO₂ adsorption capacity of the coal. In this paper, a series of CO₂ adsorption isotherm experiments were performed at different pressures and temperatures in sub-bituminous coal from the southern Junggar Basin (reservoir temperature ∼25.9°C and pressure ∼3.91 MPa). In addition, the high-pressure CO₂ adsorption characteristics of the southern Junggar Basin coal were characterized using a supercritical D-R adsorption model. Finally, the CO₂ storage capacities in sub-bituminous coal under the in situ reservoir temperature and pressure were analyzed. Results indicated that the excess adsorption capacities increase gradually with increasing injection pressure before reaching an asymptotic maximum magnitude of ∼34.55 cm³/g. The supercritical D-R adsorption model is suitable for characterizing the excess/absolute CO₂ adsorption capacity, as shown by the high correlation coefficients > 0.99. The CO₂ adsorption capacity increases with declining temperature, indicating a negative effect of temperature on CO₂ geological sequestration. By analyzing the statistical relationships of the D-R adsorption fitting parameters with the reservoir temperature, a CO₂ adsorption capacity evolution model was established, which can be further used for predicting CO₂ sequestration potential at in situ reservoir conditions. CO₂ adsorption capacity slowly increases before reaching the critical CO₂ density, following a rapid decrease at depths greater than ∼800 m in the southern Junngar Basin. The research results presented in this paper can provide guidance for evaluating CO₂ storage potential in deep coal seams.

CCUS（碳捕获、利用和储存）技术被认为是全球实现碳中和的底层方法。深层煤储层中的CO ₂封存是 CCUS 的可行选择，其封存潜力可归因于煤的CO _{2吸附能力。}本文对南准噶尔盆地次烟煤（储层温度~25.9℃，压力~3.91 MPa）进行了一系列不同压力和温度下的CO _{2吸附等温线实验。}此外，利用超临界DR吸附模型表征了准噶尔盆地南部煤的高压CO _{2吸附特性。}最后，CO ₂分析了原位储层温度和压力下次烟煤的储存能力。^{结果表明，在达到~34.55 cm 3} /g的渐近最大值之前，过剩吸附容量随着注入压力的增加而逐渐增加。超临界 DR 吸附模型适用于表征过量/绝对 CO ₂吸附容量，如 > 0.99 的高相关系数所示。CO ₂吸附量随温度降低而增加，表明温度对CO _{2有负面影响}地质封存。通过分析DR吸附拟合参数与储层温度的统计关系，建立了CO ₂吸附容量演化模型，可进一步用于预测原位储层条件下CO ₂封存潜力。CO ₂吸附容量在达到临界 CO ₂密度之前缓慢增加，随后在准噶尔盆地南部深度大于 ~ 800 m 处迅速减少。本文的研究结果可为评估深层煤层中CO _{2封存潜力提供指导。}