Performance of geopolymer as adsorbent on desulphurization of heavy gas oil

Abstract

Geopolymer is a porous aluminosilicate material and chemically similar to zeolites. As a low‐cost construction material, its suitability for adsorptive desulphurization (ADS) was studied using a petroleum feedstock. Geopolymer was produced by alkali activation of metakaolin and characterized by BET, NH3–TPD, SEM, FTIR, XRD, and XPS. The XRD and SEM studies evidenced the amorphous nature of geopolymer and the existence of macro‐ and mesopores. The XPS and NH3–TPD studies revealed the presence of surface Na and Al, and strong acid sites, respectively, in the prepared geopolymer. These sites interact with sulphur compounds of heavy gas oil through π‐π and acid–base interactions. The geopolymer showed a high sulphur adsorption capacity of 38.4 mg/g. The effects of adsorption parameters such as operating temperature, amount of adsorbent, and time for absorption on the adsorption capacity were examined using the Box–Behnken design statistical model. All three operating parameters significantly influenced the sulphur adsorption capacity of geopolymer. The adsorption of sulphur compounds on the geopolymer followed pseudo‐first‐order kinetics and did not affect its structural stability. Finally, the thermodynamic study revealed that adsorption of sulphur compounds on the geopolymer was spontaneous and exothermic.

Renewable fuel intermediates from furfural over copper-loaded mesoporous aldol condensation catalysts

“…Similarly, pvalues of <0.05 for A, B, C, A 2 , B 2 , and C 2 indicate that all three independent variables have a signicant effect on both conversion and product selectivity. 25 The interactive effect of temperature (A) and operating time (B) is evidenced by the pvalue of AB. The p-value of <0.05 shows the occurrence of a signicant interaction effect of AB on both conversion and Paper Sustainable Energy & Fuels product selectivity.…”

Cu/ZSM5-Geopolymer 3D-Printed Monoliths for the NH3-SCR of NOx

“…The Cu/GP sample showed a rather flat TPD profile, suggesting that this sample had a negligible ammonia adsorption capacity, in contrast with Li et al [28], who evaluated an adsorption capacity of 1.75 mmol/g, whereas Saha et al [46] calculated a capacity as high as 2.14 mmol/g for metakaolin-based geopolymers either in H-or alkaline-form. This is possibly caused by the residual presence of basic compounds on the surface of the Cu/GP sample.…”

“…However, the larger GP content in the Cu/GP-Z(37) composite seemed to affect the acid character of the zeolite fraction, particularly by reducing the number of strong acid sites capable of releasing ammonia above 320 • C. Furthermore, TPD profiles recorded for mechanical mixtures of pure Cu/Z and Cu/GP materials (Figure 5) showed similar qualitative features, but lower amounts of NH 3 desorption with respect to their composite monolith counterparts; this suggests that the intimate contact between the GP and ZSM5 phases established during the preparation of monoliths can favour the elimination of alkaline residues from the GP matrix. The Cu/GP sample showed a rather flat TPD profile, suggesting that this sample had a negligible ammonia adsorption capacity, in contrast with Li et al [28], who evaluated an adsorption capacity of 1.75 mmol/g, whereas Saha et al [46] calculated a capacity as high as 2.14 mmol/g for metakaolin-based geopolymers either in H-or alkaline-form. This is possibly caused by the residual presence of basic compounds on the surface of the Cu/GP sample.…”

Research and Application Progress of Geopolymers in Adsorption: A Review

“…The study revealed the presence of Na, Al, and strong acid sites on the surface of the prepared geopolymer. These sites interact with sulfur compounds in heavy gas oils through π–π and acid–base interactions [ 116 ].…”