Preparation of rGO/ZrP as a new adsorbent in dibenzothiophene removal from n-decane with high capacities and good regenerability

摘要

In this work, reduced graphene oxide (rGO)/zirconium phosphate (ZrP) nanosheets were prepared by intercalation of graphene oxide (GO) between ZrP layers followed by its reduction to rGO. Then, the adsorption behavior of the rGO/ZrP toward dibenzothiophene (DBT) was investigated. rGO/ZrP nanosheets were characterized by FT-IR, FESEM, Raman, BET and XRD analyses. The FESEM technique revealed the nano-structure of the rGO/ZrP composite and the composite has a high specific surface area of 321 m(2) g(-1). ZrP was used to prevent the reunion of reduced graphene oxide (rGO) during adsorption and storage, also increasing the specific surface area of the adsorbent. rGO/ZrP could decrease the DBT concentration from 500 ppmw to 322 ppmw after 4 h and the maximum adsorption capacity of DBT onto the rGO/ZrP was 46.6 mg g(-1) adsorbent. The effect of desulfurization temperature, initial concentration of DBT, duration of adsorption and regeneration of the adsorbent was investigated. The DBT removal efficiency of the rGO/ZrP adsorbent was nearly constant during the five consecutive cycles of the adsorption-desorption process. pi-pi interactions between rGO sheets and DBT molecules are greatly enhanced due to the pillared structure of the rGO/ZrP adsorbent. Desulfurization results were very satisfactory and rGO/ZrP could serve as a promising sorbent for the removal of DBT from petroleum.