The weight loss before and after 300 °C was related to water evaporation and char combustion, respectively . The amount of carbon accumulated on the zeolite after 100 hours of reaction under CO2/H2/toluene atmosphere was only 2.4%, whereas the amount of carbon accumulated on the zeolite after 60 hours of reaction under ethylene and toluene atmosphere reached 8.0% (Fig. ). This was probably owing to that a hydrogenrich atmosphere as well as the water produced by the in-situ hydrogenation of CO2 during the CO2/H2/toluene reaction could help to inhibit carbon deposition . This demonstrated the significant advantages of using CO2 and H2 as a feedstock compared with using light olefins as alkylating agent directly.