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Evaluation of adsorbent integrity over thousands of cycles is necessary to establish the service time and sustainability of adsorbents employed in industrial dehydration. Herein, an adsorption apparatus for rapidly cycling multiple adsorbents through a thermal swing adsorption process is introduced with results for 2000 cycles. This apparatus has eight sample cells arranged in parallel, which are embedded in an aluminum block for rapid heating and cooling. At the outlet of each cell, the water content and temperatures are measured using capacitance relative humidity sensors, which incorporate resistance thermometers. The analysis of the breakthrough curves generated for each adsorbent gives inference into the change in water uptake capacity over continuous cycling. To handle the large sets of data generated by this instrument, an automated analysis program was implemented. To demonstrate the functionality of the instrument, zeolites 4A and 13X were cycled in a thermal swing process over 2000 cycles and the change in the uptake capacity was monitored by the analysis of the breakthrough plots for each cycle. Furthermore, the results of the breakthrough analyses were verified with the thermogravimetric analysis of the adsorbents. From these experiments, zeolites 4A and 13X were observed to lose 7 ± 3 and 19 ± 7% of the adsorption capacity, respectively.

The degradation of desiccants is important in designing natural gas conditioning processes. Previous studies have focused on the effect of changes in regeneration gas water content, regeneration temperature and number...

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Activated carbon (AC) materials are porous structures generated by activation of either pyrolyzed plant or coke materials through physical or chemical means. While being widely used in industry for water, air, and product purification, ACs also may be suitable for the removal of pollutants from flue gas or sulfur compounds from natural gas fuels before combustion, provided the processes/materials are economic. ACs derived from petroleum coke (petcoke) that is often stranded and considered a low-quality byproduct are relatively inexpensive. To date, the pure component adsorption and selectivities for AC from petcoke have not been reported and compared to other reported ACs for practical application with flue gas, sour gas, or acid gas purification. Here we show that an AC from petcoke displays both high-selectivity and capacity toward SO2 and H2S. Single component volumetric adsorption experiments show adsorption as high as 554 mg g–1 for SO2 at p = 0.56 bar and 256 mg g–1 for H2S at p = 1 bar (T = 25 °C). This SO2 uptake is 66% higher than the previous highest SO2 uptake on an AC and 39 times as selective toward SO2 versus N2. These results suggest that AC from petcoke is an excellent material for recovering sulfur compounds from industrial flue gas or raw fuel, with the benefit of making use of a petroleum solid waste.