Alkylphenols and their Ethoxylates

Rose, A., C. Nistor, J. Emneus, et al. 2002. GDH biosensor based off-line capillary immunoassay for alkylphenols and their ethoxylates. Biosens. Bioelectron. 17 1033-1043. 

Alkylphenols and their ethoxylates Immunosensor using electrochemical transduction mg L 1 range 19... 

Ethoxylated alcohols and alkylphenols Sorbitan esters and their ethoxylates Sucrose esters and their ethoxylates... 

The theory of regular solutions applied to mixtures of aromatic sulfonate and polydispersed ethoxylated alkylphenols provides an understanding of how the adsorption and micellization properties of such systems in equilibrium in a porous medium, evolve as a function of their composition. Improvement of the adjustment with the experimental results presented would make necessary to take also in account the molar interactions of surfactants adsorbed simultaneously onto the solid surface. 

Vega Morales T, Torres PadronME, Sosa FerreraZ, Santana Rodriguez JJ (2009) Determination of alkylphenol ethoxylates and their degradation products in liquid and solid samples. TrAC,... 

Jahnke, A., Gandrass, J., Ruck, W. (2004). Simultaneous determination of alkylphenol ethoxylates and their biotransformation products by liquid chromatography/electrospray ionisation tandem mass spectrometry. J. Chromatogr. A 1035(1), 115-122. 

Staples CA, Naylor CG, Williams JB, Gledhill WE (2001) Ultimate biodegradation of alkylphenol ethoxylates surfactants and their biodegradation intermediates. Environ Toxicol Chem 20 2450-2455... 

The trend of discovering the analytical field of environmental analysis of surfactants by LC-MS is described in detail in Chapters 2.6-2.13 and also reflected by the method collection in Chapter 3.1 (Table 3.1.1), which gives an overview on analytical determinations of surfactants in aqueous matrices. Most methods have focused on high volume surfactants and their metabolites, such as the alkylphenol ethoxylates (APEO, Chapter 2.6), linear alkylbenzene sulfonates (LAS, Chapter 2.10) and alcohol ethoxylates (AE, Chapter 2.9). Surfactants with lower consumption rates such as the cationics (Chapter 2.12) and esterquats (Chapter 2.13) or the fluorinated surfactants perfluoro alkane sulfonates (PFAS) and perfluoro alkane carboxylates (PFAC) used in fire fighting foams (Chapter 2.11) are also covered in this book, but have received less attention. 

SPECTROMETRY—III. NON-IONIC SURFACTANTS LC-MS AND LC-MS-MS OF ALKYLPHENOL ETHOXYLATES AND THEIR DEGRADATION PRODUCTS... 

In this chapter, all four types of sediment and sludge sample handling techniques for non-ionic surfactants will be discussed and compared. Most of the studies published on non-ionics focus on APEOs and their degradation products, viz. the alkylphenols, but some extraction methods for alcohol ethoxylates (AEOs) and coconut diethanol amides will also be discussed. 

Nonionic surfactants contain (Fig. 23) no ionic functionalities, as their name implies, and include ethylene oxide adducts (EOA) of alkylphenols and fatty alcohols. Production of detergent chain-length fatty alcohols from both natural and petrochemical precursors has now increased with the usage of alkylphenol ethoxylates (APEO) for some applications. This is environmentally less acceptable because of the slower rate of biodegradation and concern regarding the toxicity of phenolic residues [342]. 

These compounds yield by their biodegradation the more toxic 4-nonylphenoT . Owing to their poor ultimate biodegradability and the possible environmental hazard of their metabolites, alkylphenol ethoxylates have been replaced in household applications, mainly by alcohol ethoxylates. However, for industrial applications, this replacement has not been carried out yet due to the excellent performance of alkylphenol ethoxylates and their low production costs . 

Nonionic surfactants like alkylphenol ethoxylates (APEO) and their biodegradation products alkylphenol diethoxylate (AP2EO), alkylphenol monoethoxylate (APIEO), and AP are isolated from aqueous solutions with a number of different stationary phases. Kubeck et al. ° used C18 cartridges to adsorb NPEO, but first the water samples were passed through a mixed-bed ion exchange resin to remove all ionic species. Eor SPE of alcohol ethoxylates (AEO) C8 cartridges have been successfully applied from which the surfactants were eluted with methanol followed by... 

Commercial alkylphenol ethoxylates come with almost 100 % surfactant content or with rheological modifiers. Their consistency changes from liquid via paste to solid wax as ethoxylation number rises. Isooctylphenol and isononylphenol ethoxylates with m <4 are oil-soluble, those with m = 4-5 form emulsions in water, and products with m > 5 form clear aqueous solution. 

Simultaneously with the use of PBI for the analysis of pesticides and agrochemicals, both dispersed in large quantities in the environment [109], this interface type was also appHed to perform the determination of a broad spectrum of pollutants generated by degradation processes, mobilized from waste disposals and contained in the leachates [110] and finally found in the aquatic environment The analysis of 500 L samples of drinking water made the pollution of these waters with alkylphenol ethoxylates (APEOs) and alkylphenol carboxylates (APECs) obvious [111]. As polar constituents of wastewater samples non-ionic surfactants of NPEO type and their acidic metaboHtes, plasticizers, and plastic additives could be confirmed by the appHcation of PBI-LC-MS [112]. 

Among different nonionic surfactant classes, alkyl-phenol ethoxylates (APEOs) comprise the class meriting special attention with respect to environmental issues. The analysis of underivatized alkylphenolic compounds by GC-MS is restricted to the most volatile degradation products, such as alkylphenols and APEOs with less then 4-ethoxy groups. To overcome the problem of volatility, different offline and online derivatization protocols have been developed. Two complementary MS techniques, one using El and another using the less commonly used positive (P)CI, have been evaluated for the analysis of APEOs, their acidic (APECs) and neutral metabolites (APs), and halogenated derivatives. 

The most widely used alkylphenols in the manufacture of nonionic surfactants are described as follows in the order of their importance. APEs derived from p-nonylphenol account approximately 80% of the total market whereas those derived from octyl phenol account for 15-20%. Dodecyl phenol, di-nonylphenol, and DSBP ethoxylates run a poor third at <5%. 

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