Abstract:
Amid the global strategic push for carbon neutrality, reducing carbon dioxide (CO
2) emissions has become a central task in the green and low-carbon transformation of the chemical industry. As a major carbon-intensive sector, the chemical industry urgently needs to break away from conventional, carbon-locked pathways and redefine CO
2 from a waste product into a strategic raw material for resource utilization. Currently, CO
2 chemical utilization primarily focuses on two main platforms: syngas and direct methanol synthesis. Among these, three technological pathways—dry reforming of methane (DRM), reverse water-gas shift (RWGS), and CO
2 hydrogenation to methanol—have attracted the most attention. Research indicates that these pathways face significant challenges in thermodynamics, reaction mechanisms, and catalyst performance. Although DRM can synergistically consume both CH
4 and CO
2, its strongly endothermic nature requires high-temperature operation, leading to high energy consumption, stringent equipment requirements, and rapid deactivation of nickel-based catalysts due to coking and sintering. Noble metals offer better stability but are limited by cost. The RWGS reaction efficiently converts CO
2 to CO at medium-to-high temperatures but faces intense competition from side reactions such as methanation, placing higher demands on catalyst selectivity, while high temperatures still exacerbate catalyst deactivation. In contrast, direct CO
2 hydrogenation to methanol is thermodynamically more favorable at lower temperatures but is constrained by low equilibrium conversion and the hydrothermal deactivation of copper-based catalysts by water generated in the reaction. In recent years, novel oxide catalysts such as In
2O
3 and ZnO–ZrO
2 have demonstrated excellent methanol selectivity and long-term stability, offering new directions for technological breakthroughs. However, economic viability remains the core bottleneck constraining large-scale commercialization. Currently, the cost of green hydrogen constitutes the major cost component of CO
2 hydrogenation pathways. Coupled with CO
2 capture costs, this renders the price of green methanol or syngas products significantly higher than that of traditional fossil fuel-based routes. Even under optimized process conditions, their market competitiveness heavily depends on reductions in renewable electricity prices, improvements in electrolyzer efficiency, and the refinement of carbon pricing mechanisms. At the policy level, strong fiscal incentives are crucial for bridging the cost gap and accelerating the deployment of demonstration projects. In the long term, achieving efficient and high-value utilization of CO
2 requires multi-dimensional synergy: on one hand, advancing catalyst durability and activity through cutting-edge catalytic material design, such as single-atom catalysis and interface engineering; on the other hand, driving down costs in the green hydrogen supply chain and establishing a unified, transparent carbon accounting and certification system. Only through the combined force of technological breakthroughs, cost reduction, and policy support can CO
2 chemical utilization truly transition from a “potential pathway” to a “mainstream solution”, providing practical and viable industrial support for the global carbon neutrality goal.