Effect of Hydrochloric Acid on Sampling and Analysis of Semivolatile Organic Compounds in Incineration Flue Gas. 1. Chlorophenols

Abstract

The recoveries of 16 isomers of chlorophenols (CPs) from the adsorbent (XAD-2) of the MM5 train are affected by hydrochloric acid (HCl) present in the incinerator flue gas. At 2.05 and 5.53 mg/L in flue gas, HCl caused desorption of CPs from XAD-2. The desorption is dependent upon the number of chloro substituents in the CPs. The Soxhlet extraction behaviors of CPs from XAD-2 in the presence or the absence of HCl were also studied in the laboratory. The results explain the previously reported low recovery of pentachlorophenol from XAD-2 when the flue gas contained none or very low concentrations of HCl. An extraction procedure for complete CPs recoveries from XAD-2 is proposed that involved two sequential extractions: first with dichloromethane and then with the addition of 1.0 mL of 1.0 M aqueous HCl on XAD-2 and followed by the subsquent extraction with dichloromethane. This procedure does not affect other semivolatile compounds on XAD-2 and leads to [13C6]pentachlorophenol surrogate recovery of 90 ± 6%. An extraction anomaly of CPs using dichloromethane from the combined synthetic acidic condensate and acidic ethylene glycol is presented. Toluene is suggested as the solvent for complete CPs extraction from the combined liquids. This acid effect led to a suggestion of using at least one surrogate isomer for each CP group on XAD-2 of the MM5 train.

Effect of Hydrochloric Acid on Sampling and Analysis of Semivolatile Organic Compounds in Incineration Flue Gas. 3. Chlorobenzenes and Polychlorinated Biphenyls

“…Chemicals. XAD-2 was purified according to the previous procedures (2) and used immediately for flue gas sampling. All solvents have been specified earlier (2).…”

“…XAD-2 was purified according to the previous procedures (2) and used immediately for flue gas sampling. All solvents have been specified earlier (2). Silica (Bio-Sil A, 100-200 mesh, Bio-Rad) was purified according to the previously reported procedure (3).…”

“…The acid effects on sampling and analysis of the 16 CPs (2) and the 16 PAHs (3) in incineration flue gas have been reported previously. When the concentrations of oxygen (10%), moisture (14%), and carbon dioxide (7%) are kept constant, HCl at 0.17 mg/L [an upper limit model of scrubbed flue gas (1)] does not affect the recoveries of CPs and PAHs from the XAD-2 of MM5 train (2,3). However, higher concentrations of HCl (2.05 and 5.53 mg/L) cause desorption of some CPs from the XAD-2 (2).…”

“…When the concentrations of oxygen (10%), moisture (14%), and carbon dioxide (7%) are kept constant, HCl at 0.17 mg/L [an upper limit model of scrubbed flue gas (1)] does not affect the recoveries of CPs and PAHs from the XAD-2 of MM5 train (2,3). However, higher concentrations of HCl (2.05 and 5.53 mg/L) cause desorption of some CPs from the XAD-2 (2). The CPs with a smaller number of chloro substituents are more affected by the acid (2).…”

Derivative spectrophotometry in the analysis of mixtures of phenols and herbicides

“…The methods and their applications to the determination of various pesticides have been reported by Sherma [1][2][3] and others. [4][5][6][7] Urea, triazine and uracil derivatives of herbicides [8][9][10][11][12] and methyl-and chlorophenols [13][14][15][16][17][18][19][20] have also been determined by GC. Apart from GC, HPLC and spectrophotometric methods are frequently used in these determinations.…”