Detergent production

Of the higher alkyinaphthalenes, those of importance are the amyl-, diamyl-, polyamyl-, nonyl-, and dinonylnaphthalenes. These alkyinaphthalenes are used in sulfonated form as surfactants and detergent products. 

Alkenes. The sulfation of low molecular weight alkenes using concentrated sulfuric acid is amenable to continuous operation. Good agitation is required and the reaction is performed at 70—80°C. Dialkyl sulfates ate also formed. Longer (C 2 i8) carbon chain alkenes yield detergent products. Order... 

Ethoxylated andSulfatedAlkylphenols. Because these aLkylphenols degrade less readily than the sulfated alcohol ethoxylates, their anticipated expansion failed to materialize, although by 1965 they were widely used in retail detergent products. Sulfated alkylphenol ethoxylates are used in hospital cleaning products, textile processing, and emulsion polymerization. Sulfated alkyphenol ethoxylates are sold as colorless, odorless aqueous solutions at concentrations of >30%. The presence of ethylene oxide in the molecule increases resistance to hardness ions and reduces skin irritation. Representative commercial sulfated alkylphenol ethoxylates are given in Table 12. 

In acidic media, amine oxides and anionic surfactants form precipitates the CMC is much greater than in neutral or alkaline media. Change in CMC parallels change from ionic to nonionic form. Amine oxides are stable in formulated detergent products and do not act as oxidizing agents. Composition and function of representative commercial amine oxides are given in Table 26. 

The perhydrolysis reaction could theoretically continue to give four moles of peracid per mole of TAED but stops at this stoichiometry because of the substantial increase in the conjugate acid pify of the leaving group going from an amide (p-R = 17) to an amine (pif = 35) (94,95). Nonanoyloxybenzene sulfonate (NOBS) [101482-85-3] is used in detergent products in the United States and Japan. The NOBS perhydrolysis reaction is shown in equation 20 (96). 

Health and Safety Factors As a class, surfactants and detergent products are among the most widely used chemical compositions. Almost everyone is exposed to these products on a daily basis ia situatioas that range from ingestion of food-grade emulsifiers to intimate coatact of skin and eyes with personal-care and laundry products. Safety is therefore a matter of great importance (132,133). Ranges of surfactant LD q values are shown ia Table 2. 

Under conditions of normal use, detergent products are not lia2ardous to users. Nonetheless, surfactants possess some toxicity, and they are mild irritants. Particularly under conditions of misuse, such as accidental ingestion or spillage, they can produce irritation and discomfort in the form of nausea and vomiting, as well as irritation to skin and eyes. The long-term effects, however, are minimal (134). 

The range of values for several representative categories of detergent products is given in Table 4. ... 

Table 4. Acute Oral Ranges for Detergent Product ...

Methods of testing for eye and skin irritation potential have been reviewed (137). The official FHSA procedure for evaluating ocular irritation potential of detergent products is a modified Drai2e rabbit eye test (138). Some controversy surrounds this method at present, and a search for a procedure less injurious to test animals is in progress. In general, the order of irritation is cationic > anionic > nonionic (139). 

The introduction of surfactant products into the environment, after use by consumers or as part of waste disposed during manufacture, is regulated by the Clean Water Act, the Clean Air Act, and the Resource Conservation and Recovery Act. In this respect, surfactants are subject to the same regulations as chemicals in general. There are, however, two areas of specific relevance to surfactants and detergent products, ie, biodegradabiUty and eutrophication. 

While many industrial wastes are so low in nitrogen and phosphorus that these must be added if biologically based treatment is to be used, others contain very high levels ofthese nutrients. For example, paint-production wastes are high in nitrogen, and detergent production wastes are high in phosphorus. Treatment for removal of these nutrients is required in areas where eutrophication is a problem. 

Longman, G. F. The Analysis of Detergents and Detergent Products. J. Wiley Sons, Ltd., Chichester 1975. 

Normal paraffins in this range are important intermediates for alkylating benzene for synthetic detergents production (Chapter 10). They are also good feedstocks for single-cell protein (SCP). 

Urea possesses a unique property of forming adducts with n-paraffms. This is used in separating C12-C14 n-paraffms from kerosines for detergent production (Chapter 6). 

Monochloroparaffins in this range may be dehydrochlorinated to the corresponding monoolefms and used as alkylating agents for the production of biodegradable detergents. Alternatively, the monochloroparaffins are used directly to alkylate benzene in presence of a Lewis acid catalyst to produce alkylates for the detergent production. These reactions could be illustrated as follows ... 

Alkylation of benzene using alpha olefins produces linear alkylbenzenes, which are further sulfonated and neutralized to linear alkylbenzene sulfonates (LABS). These compounds constitute, with alcohol ethoxy-sulfates and ethoxylates, the basic active ingredients for household detergents. Production of LABS is discussed in Chapter 10. 

Physical Properties and Behavior of Linear Alkylbenzenesulfonates in Mixtures with Other Surfactants in Household Detergent Products... 

The information presented in this chapter is intended to provide a brief overview of the composition, performance, and formulation properties of LAS by itself and in combination with other surfactants. The particular performance synergies and processing characteristics of certain combinations of surfactants are discussed briefly. The examples of mixed active formulations provided herein represent to the best of the author s knowledge the approximate levels of major surfactants in actual household detergent products both past and present. This does not imply that these formulations are complete because many additives, such as bleaches, enzymes, builders, hydrotropes, thickeners, perfumes, and coloring agents, may also be present in varying amounts. 

In formulating liquid detergent products with LAS, the carbon chain distribution, phenyl isomer distribution, and DATS level can all contribute to the solubility and viscosity characteristics. Hydrotrope requirements for isotropic liquid detergents can vary widely for different types of commercial LAS. 

As detergent manufacturers responded to consumer trends the number of mixed active detergent products increased. The combination of LAS with other surfactants in mixed active systems can provide several advantages over a single active LAS system. These advantages can include the following ... 

Improved formulation characteristics in liquid detergent products... 

For reasons of performance, feedstock economics, and processing versatility, LAS will continue in the future to be a major component of mixed active detergent products. 

The simultaneous reaction of sulfur dioxide and chlorine with paraffins, named sulfochlorination, was discovered by Reed and Horn in the 1930s [9]. The primary products of this reaction are the alkanesulfochlorides [10], which can be saponified to alkanesulfonates by sodium hydroxide solution or treated with substituted phenolates to give plasticisers. In a short time the process was industrially realized to secure detergent production during World War II in Germany [11]. 

---