In this work, amine-impregnated activated carbon was prepared from oil sands coke, for use in CO 2 capture. Delayed oil sands coke was activated using microwave heating and KOH as activation agent. The resulting material was then impregnated with one of diethanolamine, methyl diethanolamine, or tetraethylene pentamine. Analysis of the bulk and surface composition of the impregnated samples using elemental analysis and X-ray photoelectron spectroscopy suggested that the amines were deposited on the surface of the activated carbon. Materials impregnated with diethanolamine performed best for CO 2 capture; the highest adsorption capacity achieved was 5.63 mmol CO 2 /g adsorbent for activated carbon impregnated with 1.15 mmol N/g activated carbonnearly 75% higher than reported values for zeolite 13X. Adsorption of CO 2 on the amineimpregnated activated carbon at 40, 50, 60, and 75 °C showed that the highest adsorption capacity was obtained at 50 °C. Using oil sands delayed coke as a precursor for activated carbon transformed a petroleum waste material into an effective CO 2 adsorbent. Modifying the prepared activated carbon with amines improved CO 2 uptake capacity, creating a useful adsorbent for potential use in CO 2 capture.

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Five-cycle adsorption/regeneration experiments using 1,2,4-trimethylbenzene (TMB) were completed at different purge gas flow and heating rates to identify their impact on heel buildup. Regeneration of a saturated activated carbon fiber cloth was completed at 400 °C using resistive heating at different heating rates and purge gas flow. At 1 standard liter per minute (SLPM) desorption purge gas, increasing the regeneration heating rate from 5 to 100 °C/min increased heel buildup from 4.6 to 10.4 wt % and adsorption capacity loss from 7.8 to 52.0%. On the other hand, at 70 °C/min heating rate, increasing the purge gas flow rate from 0.1 to 5 SLPM decreased heel buildup from 14.6 to 1.4% and capacity loss from 82.3 to 2.1%. Increasing the heating rate or decreasing the purge gas flow results in higher TMB concentrations being exposed to the high desorption temperature and higher residence time of TMB in the adsorbent pores. This increases adsorbate decomposition, causing deposition of pore-blocking, high carbon content residue (coke) onto the adsorbent surface. These results show the importance of optimizing desorption conditions to minimize heel buildup during cyclic use, contrary to conventional wisdom, suggesting that higher heating rates are consistently preferred, and provide improvements in energy use.

We report the propane dehydrogenation behavior of catalysts prepared using wet impregnation method that immobilize Pt nano cluster on the alumina surface. The immobilization of the metal particles and their nano size dimensions were demonstrated by transmission electron microscopy. Selectivity to propylene for these catalysts is comparable to those obtained over industrial Pt catalysts, yet the resistance to deactivation by carbon poisoning is much greater for our catalysts. The deactivation behavior is more typical of traditionally prepared PtSn catalysts on γ-alumina than of catalysts supported onθ-alumina.