Alkylphenol in water

The solubihty of alkylphenols in water falls off precipitously as the number of carbons attached to the ring increases. They are generally soluble in common organic solvents acetone, alcohols, hydrocarbons, toluene. Solubihty in alcohols or heptane follows the generalization that "like dissolves like." The more polar the alkylphenol, the greater its solubihty in alcohols, but not in ahphatic hydrocarbons likewise with cresols and xylenols. The solubihty of an alkylphenol in a hydrocarbon solvent increases as the number of carbon atoms in the alkyl chain increases. High purity para substituted phenols, through Cg, can be obtained by crystallization from heptane. 

Navarro A, Tauler R, Lacorte S et al (2010) Occurrence and transport of pesticides and alkylphenols in water samples along the Ebro River Basin. J Hydrol 383 18-29... 

BPA has increasingly been analyzed together with alkylphenols in water by LC-MS/ MS under NI conditions [73,75,76]. The ions used in LC-MS/MS for detection under multiple reactions monitoring (MRM) mode were the following the deprotonated molecular ion m/z 227 [M H] and its two daughter ions m/z 133 and 212. 

The aromatic ring of alkylphenols imparts an acidic character to the hydroxyl group the piC of unhindered alkylphenols is 10—11 (2). Alkylphenols unsubstituted in the ortho position dissolve in aqueous caustic. As the carbon number of the alkyl chain increases, the solubihty of the alkah phenolate salt in water decreases, but aqueous caustic extractions of alkylphenols from an organic solution can be accomphshed at elevated temperatures. Bulky ortho substituents reduce the solubihty of the alkah phenolate in water. The term cryptophenol has been used to describe this phenomenon. A 35% solution of potassium hydroxide in methanol (Qaisen s alkah) dissolves such hindered phenols (3). 

Commercial alkylphenol ethoxylates are almost always produced by base-cataly2ed ethoxylation of alkylphenols. Because phenols are more strongly acidic than alcohols, reaction with ethylene oxide to form the monoadduct is faster. The product, therefore, does not contain unreacted phenol. Thus, the distribution of individual ethoxylates in the commercial mixture is narrower, and alkylphenol ethoxylates are more soluble in water. 

The polymeric latex obtained in a hydrophobic organic solvent is poorly dispersed in water because of the presence of an emulsifier with a low HLB value. For this reason, a wetting agent is added to water or emulsion prior to the dissolution. The wetting agent (a surface active substance with a high HLB value) facilitates the inversion of latex phases to produce a direct type emulsion. Usually, it belongs to oxyethylated alkylphenols, fatty alcohols, or fatty acids. 

Linear Alkylbenzene Sulphonates (LAS) and Alkylphenol Ethoxylates (APE) in Waters, Wastewaters and Sludges by High... 

Oil-in-water emulsions provide a cost-effective alternative to the methods mentioned previously, namely, heating or diluting. A typical transport emulsion is composed of 70% crude oil, 30% aqueous phase, and 500 to 2000 ppm of a stabilizing surfactant formulation [1497]. Nonionic surfactants are relatively insensitive to the salt content of the aqueous phase ethoxylated alkylphenols have been used successfully for the formation of stable emulsions that resist inversion. 

Mixtures of aqueous emulsions of oil can be more effectively transported through pipelines if certain antifreeze formulations are added to the system. Stable oil-in-water emulsions for pipeline transmission by using 0.05% to 4% ethoxylated alkylphenol as an emulgator and a freezing-point depressant for water enable pipeline transmission at temperatures below the freezing point of water [736]. 

It is important that any method for surfactant analysis maintains the same oligomer distribution in the extracted samples. LLE and SPE are generally combined with chromatographic methods for separation and resolution of non-ionic surfactants into their ethoxamers. An alternative is the use of SPME-HPLC, recently reported by Chen and Pawliszyn [141]. Alkylphenol ethoxylate surfactants such as Triton X-100 and various Rexol grades in water were determined by means of SPME-NPLC-UV (at 220 nm) [142]. Detection limits for individual alkylphenol ethoxamers were at low ppb level. 

Addition of a chlorine causes a drop in chlorophenol solubility in water by about 0.62 log units, and KoW increases by about 0.78 log units. For the alkylphenols, addition of a methylene causes about a 0.50 log unit drop in solubility in water, and KoW increases by only about 0.36 log units. The slope of the log Kow versus solubility lines are thus about 0.78/0.62 or 1.25 for the chlorophenols and 0.36/0.5 or 0.72 for the alkylphenols. An implication is that since KqW can... 

Another approach consists of an in-situ acetylation and extraction of NPEOs and further analysis of the acetyl derivatives. The method has been applied to analyse effluent water and sewage sludges [102,103], sediments [104] and river waters [105]. Silylated derivatives [106] using BSA or BSTFA have also been used to determine NPEO (n < 6) in seawater [107] and wastewater [107,108], sediments [109] and sludges from wool scour effluents [110]. Halogenated derivatives of alkylphenols (AP) can also be formed as a result of chlorination practices in water treatment or wastewater if bromide is present. Brominated OPs and NPs (BrAPEOs) have been identified by GC-MS in sewage [111] and tap water [89], respectively. 

Fig. 6.2.3. Seasonal variation of alkylphenolic compounds in water (A) and sediment (B) samples from the Anoia river. Sampling points A1 (1.5 km upstream of WWTP, Igualada) A2 (23 km downstream of WWTP) A3 (27 km downstream of WWTP).

However, an issue of concern is the relatively high level of alkylphenolic compounds in both water and sediment upstream of known sources of pollution (WWTPs). The concentrations of total alkylphenolic compounds (APEO, AP and APEC) ranged from 5 to 15 jxg L-1 in water and from 0.075 to 0.55 xg g-1 in sediments, and may be attributed mainly to two origins. One is the use of sewage sludge in agriculture and the other is the uncontrolled discharge of industrial wastewaters in the upper course of the river. 

Table 16.7 shows the depletion of alkylphenols from crude oil, by dissolution in water, after equilibration of the crude oil with deionised water at a pressure of... 

Table 16.7 Comparisons of alkylphenol concentrations (mg/L), determined by RP-HPLC-ED after isolation by SPE of Miller oil, equilibrated oils at 25°C and 125°C, and corresponding water samples (after Bennett and Latter, 1997). Coelution of compounds determined by cochromatography with authentic standards 3,5-DMP + 4-ethylphenol 3,4-DMP + 3-ethylphenol 2,3-DMP + 2-ethylphenol Sum of concentrations in equilibrated oil and corresponding water. Reprinted from Bennett B, Latter SR (1997) Partition behaviour of alkylphenols in crude oil brine systems under subsurface conditions. Geochim Cosmochim Acta 61 4393-4402. Copyright 1997 with permission of Elsevier... 

Bennett and Larter (1997) also studied the solvation of alkylphenols in crude oil-water systems at equilibrium to obtain partitioning coefficients under variable temperature, pressure, and water salinity concentration. Alkylphenol depletion from crude oil, expressed by phenol, cresols, and 3,5 dimethyl phenol, versus temperature in a range of 25-125°C, is given in terms of partition coefficient (P) values (Fig. 16.22). Partition coefficient values increase with addition of alkyl groups to the phenol nucleus. Note that the alkylphenol partition coefficient curves for different isomers tend to converge at higher temperatures and, as a consequence, differences between phenol and p-cresol decrease with increases in temperature. Similar results for oil-deionised water and oil-brine experiments show that increasing temperature leads to a decrease in partition coefficient values. 

Section 18.7 reports the methods for the determination of other emerging pollutants, whose presence in waters is due to the discharge of hygiene and cosmesis products, such as sunscreen, UV Liters, alkylphenol, and ethoxylate surfactants. 

Mart ianov, A.A., B.B. Dzantiev, A.V. Zherdev, et al. 2005. Immunoenzyme assay of nonylphenol Study of selectivity and detection of alkylphenolic non-ionic surfactants in water samples. Talanta 65 367-374. 

Chriswell and Cheng [65] have shown that chlorophenols and alkylphenols in the pbb to ppm range in non saline waters and treated drinking water can be determined by sorption on macroporous anion exchange resin, elution with acetone and measurement by gas chromatography. 

Destaillats H, Hung H-M, Hoffmann MR. Degradation of alkylphenol ethoxy late surfactants in water with ultrasonic irradiation. Environ Sci Technol 2000 34 311-317. 

---