Neutralization-extraction hybrid

FIG. 15-13 Example of neutralization-extraction hybrid process implemented in an extraction column. 

In their hybrid scheme (Figure 7.7), the light neutral fraction from the vacuum tower and solvent extraction steps goes directly to the solvent dewaxing unit, by-passing the hydrotreater, since their experience was that on such good quality streams, solvent extraction sufficed to make acceptable base stocks. The other two heavier waxy distillate streams are subjected to quality upgrading... 

CEC, a hybrid separation technique of CE and HPLC, potentially combines the high efficiency of CE and the selectivity and versatility of HPLC. CEC was coupled with Ru(bpy)3 " ECL detection by Xu s group for the first time. Proline, putrescine, spermidine, and spermine were separated efficiently by this method at pH range of 3.5-7.0 of the mobile phase. The proposed detection scheme offers a powerful tool for analysis since CEC generally displays better resolution than CZE for neutral analytes and charged analytes with equal electrophoretic mobilities [69]. Dual-cloud point extraction (dCPE) and tertiary amine labeling has been used for sensitive and selective detection of two auxins employing CE-ECL. The proposed method shows feasibility to the detection of the two auxins in acacia tender leaves, buds, and bean sprout and the detection limits (S/N = 3) were 2.5 and 2.8 nM for indole-3-acetic acid (lAA) and indole-3-butyric acid (IBA), respectively. The proposed method was applied effectively to the detection of the two auxins in real samples [70]. 

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