Columns alternating regeneration

At times, the process stream flow must be increased after the initial installation to satisfy production demands. Depending on the magnitude of the increase, the existing system may or may not be able to handle the added flow. If it can, regeneration frequency must increase. Adding more resin to the column is often considered an alternative to installing another column. Resin addition lessens the space for backwash and may be a cause for poor column performance. 

Cyclobutanone [1191-95-3] M 70.1, b 96-97 , d 0.931, n 1.4189. Treated with dilute aqueous KMn04, dried with molecular sieves and fractionally distd. Purified via the semicarbazone, then regenerated, dried with CaS04, and distd in a spinning-band column. Alternatively, purified by preparative gas chromatography using a Carbowax 20-M column at 80°. (This treatment removes acetone). 

In the PSA process, the reformer product gas is passed through an adsorption column, where impurities are preferentially adsorbed. After a set time, the feed gas to the reactor column is diverted to a parallel column. At this stage, the first column is depressurized, allowing the bed regeneration. It is a cyclic process, the two columns being alternately pressurized and depressurized [15]. 

Despite promising initial results of good capacity (0.06 g of succinic acid/ g of sorbent), 70% recovery using hot water, and a recovered concentration of >100 g/L, the hot water regeneration was not stable over 10 cycles in a packed column. Therefore, alternative regeneration schemes using acid and base were examined for the best resins and more sorbents were reexamined at this time. 

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