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CO 2 capture performance of bifunctional activated bleaching earth (ABE) was investigated at atmospheric pressure. The sorbents were characterized by means of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Caron-Hydrogen-Nitrogen analysis (CHN), Fourier transform infrared (FT-IR) and thermal gravimetric analysis (TGA). The CO 2 capacity was enhanced via basic-modification and monoethanolamine (MEA) loading of the ABE sorbent to obtain a bifunctional surface property. Here, basic-modified calcined ABE with a 30 wt.% MEA loading (SAB-30) showed the highest CO 2 capture capacity, but this was decreased with excess MEA loading (> 30 wt.%). At a 10% ( V / V ) initial CO 2 concentration feed, the maximum capacity of SAB-30 increased from 2.71 mmol/g at 30°C (without adding moisture to the feed) to 3.3 mmol/g at 50°C when adding 10% ( V / V ) moisture to the feed. Increasing the moisture concentration further reduced the maximum CO 2 capacity due to the blocking effect of the excess moisture on the sorbent surface. However, SAB-30 could completely capture CO 2 even in a 100% ( V / V ) initial CO 2 concentration feed. A maximum CO 2 capacity of 5.7 mmol/g for SAB-30 was achieved at 30°C. Varying the ratio of sorbent weight to total flow rate of the gas stream had no discernible effect on the equilibrium CO 2 capture capacity. Avrami's equation and Toth's isotherm model provided a good fitting for the data and suggested the presence of more than one reaction pathway in the CO 2 capture process and the heterogeneous adsorption surface of SAB-30. Thermodynamics studies revealed that CO 2 capture on the bifunctional SAB-30 is feasible, spontaneous and exothermic in nature. [ABSTRACT FROM AUTHOR]

Catalytic activities of Ce–Mg promoted Cu/Al 2 O 3 catalysts via methanol steam reforming was investigated in terms of the methanol conversion level, carbon monoxide selectivity and hydrogen yield. The factors chosen were the reaction temperature, copper content, Mg/(Ce + Mg) weight-percentage and steam to carbon ratios. The catalysts were prepared by co-precipitation and characterized by means of XRD, BET, H 2 -TPR, and FESEM. The Ce–Mg bi-promoter catalysts gave higher performance due to magnesium penetration into the cerium structure causing oxygen vacancy defects on the ceria. A response-surface-model was then designed to optimize the condition at a 95% confidence interval for complete methanol conversion to a high H 2 yield with a low CO content, and revealed an optimal copper level of 46–50 wt%, Mg/(Ce + Mg) of 16.2–18.0%, temperature of 245–250 °C and S/C ratio of 1.74–1.80. No deactivation of the Cu 0.5 Ce 0.25 Mg 0.05 /Al catalyst was observed during a 72-h stability test. [ABSTRACT FROM AUTHOR]