Alkylphenols major applications

Gas chromatography (GC) has developed into the most powerful and versatile analytical separation method for organic compounds nowadays. A large number of applications for the analysis of surfactants have emerged since the early 1960s when the first GC papers on separation of non-ionics were published. The only major drawback for application of GC to surfactants is their lack of volatility. This can be easily overcome by chemical modification (derivatisation), examples of which will be discussed extensively in the following paragraphs. This chapter focuses on surfactant types, and in addition discusses some structural aspects of alkylphenol ethoxylates (APEOs) that are important for, as well as illustrative of, aspects of separation and identification that are linked to the complexity of the mixtures of surfactants that are involved. 

Figure 1.1 presents the consumption of the major surfactants in the world market in 1996. Along with soap, linear alkylbenzene sulphonates (LAS) remain the most bulky and cost-effective anionic surfactants. LAS will continue to be the workhorse of the detergents industry on a global basis. However, the LAS share decreases gradually their recess is occupied by alcohol-derived surfactants, first of all alcohol sulphates (AS), alcohol ethoxylates (AE) and alcohol ether sulphates (AES). In West Europe alkylphenol ethoxylates (APE) have been removed over the last two decades from a large number of household applications in view of... 

MAJOR ALKYLPHENOLS USED IN SURFACTANT APPLICATIONS 3.3.1 Introduction... 

The worldwide annual production of all alkylphenols exceeds 1 billion pounds. The direct use of alkylphenols is, however, limited to only a few minor applications. The vast majority of alkylphenols are used as intermediates in the synthesis of derivatives, which (in turn) have a wide range of applications ranging from surfactants to pharmaceuticals. The principal markets for alkylphenols are nonionic surfactants, lube-oil additives, phenolic resins, polymer additives, and agrochemicals. The alkylphenols that are most significant in surfactant and applications, along with their general mode of manufactme and other major commercial applications are... 

The alkylphenol p-tert-octyl phenol (PTOP) is the product of a branched-chain, eight-carbon-containing olefins, and phenol yielding the general structure as shown in Structure 3.13. The PTOP-based surfactants are used mainly in the same applications as PNP-based surfactants. In addition, a major use is as a surfactant in the emulsion polymerization of acrylic and vinyl polymers. Consumption of PTOP-based surfactants is believed to exceed 60 million lb per year. These surfactants are considered to be more of a specialty type because of the higher raw material cost of the diisobutylene as compared to nonene. 

Alkylphenol ethoxylate (APE) surfactants make up approximately 10% of overall consumption. While effective in many industrial applications, they face a number of environmental challenges that could greatly reduce their use in the future. Of major importance are questions concerning their relatively slow rate of biodegradation and the possible toxicity of degradation intermediates, especially phenols and other aromatic species. In the United States and western Europe, many detergent manufacturers have voluntarily discontinued their use in household products. 

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