DETERMINATION OF 4-NONYLPHENOL .1. OPTIMIZATION OF THE GAS-CHROMATOGRAPHIC DETERMINATION OF 4-NONYLPHENOL BY ORTHOGONAL ARRAY DESIGN AND ELECTRONIC PRESSURE PROGRAMMING

Orthogonal array design (OAD) and electronic pressure programming (EPP ) using built-in electronic pressure control (EPC) has been employed t o optimize gas chromatographic (GC) conditions to improve the separati on and detection of the isomers of 4-nonylphenol whose high toxicity t owards marine life is well documented. Seven GC parameters have been e xamined by the OAD, namely carrier gas pressure program, initial oven temperature, time duration of initial oven temperature, final oven tem perature, solvent effect, purge-on time, and two different oven heatin g rates. Two responses, normalized peak area (NPA) and number of disti nguishable peaks (NDP), were used to evaluate the suitability of OAD f or the optimization of GC performance. A good correlation between two responses was established. The optimization of these parameters in the analysis of 4-nonylphenol demonstrates the applicability of the OAD a nd EPC for environmental analysis by GC. (C) 1996 John Wiley & Sons, I nc.