In this article, we propose an original algorithm for numerical simulation of the conjugated reactive transport. The algorithm is essentially oriented toward the use of GPUs. We simulate the C O2 chemosorption by soda-lime sorbent, assuming a multi-scale process. Macropore space supports both advective and diffusive transport of the reactive species, whereas impermeable microporous sorbent granules admit diffusion as the only transport mechanism. We simulated CO₂ pass-through an evenly distributed granules illustrating agreement with lab measurements. We also studied the CO₂ break-through rates in dependence of sorbent granules compaction in the reactor.