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Alkylphenols processes

Some alkylphenol appHcations can tolerate "as is" reactor products, most significantly in the production of alkylphenol—formaldehyde resins. These resins can tolerate some of the reactant and by-product from the alkylphenol reactor because they undergo purification steps. This resin production route has both capital and operating cost advantages over using purer alkylphenol streams as feedstock. For these savings, the resin producer must operate the process in such a way as to tolerate a more widely varying feedstock and assume the burden of waste disposal of some unreactive materials from the alkylphenol process. [Pg.64]

Nickel also has been used as a dye site in polyolefin polymers, particularly fibers. When a nickel compound, eg, the stearate or bis(p-alkylphenol) monosulfide, is incorporated in the polyolefin melt which is subsequently extmded and processed as a fiber, it complexes with certain dyes upon solution treatment to yield bright fast-colored fibers which are useful in carpeting and other appHcations (189). Nickel stearate complexing of disperse mordant dyes has been studied (190). [Pg.15]

Alkylphenols can be synthesized by several approaches, including alkylation of a phenol, hydroxylation of an alkylbenzene, dehydrogenation of an alkylcyclohexanol, or ring closure of an appropriately substituted acycHc compound. The choice of approach depends on the target alkylphenol, availabihty of the starting materials, and cost of processing. The procedures discussed herein encompass commercial methods, general methods, and a few specific examples of commercial interest. [Pg.58]

Manufacture and Processing Alkylphenols of commercial importance are generally manufactured by the reaction of an alkene with phenol in the presence of an acid catalyst. The alkenes used vary from single species, such as isobutylene, to compHcated mixtures, such as propylene tetramer (dodecene). The alkene reacts with phenol to produce mono alkylphenols, dialkylphenols, and tri alkylphenols. The mono alkylphenols comprise 85% of all alkylphenol production. [Pg.62]

To describe the varied processes by which alkylphenols are produced, it is convenient to consider the reaction and recovery separately. In some cases this distinction is artificial because the operations are intimately linked, but in many processes the break is operationally significant. [Pg.62]

The complex batch reactor is a specialized pressure vessel with excellent heat transfer and gas Hquid contacting capabiUty. These reactors are becoming more common in aLkylphenol production, mainly due to their high efficiency and flexibiUty of operation. Figure 2 shows one arrangement for a complex batch reactor. Complex batch reactors produce the more difficult to make alkylphenols they also produce some conventional alkylphenols through improved processes. [Pg.63]

Purification. The method used to recover the desired alkylphenol product from the reactor output is highly dependent on the downstream use of the product and the physical properties of the alkylphenol. The downstream uses vary enormously some require no refining of the alkylphenol feedstock others require very high purity materials. Physical property differences affect both the basic type of process used for recovery and the operating conditions used within that process. [Pg.64]

Some alkylphenols in commercial production have low vapor pressures and/or low thermal decomposition temperatures. Eor these products, the economics of distillation are poor and other recovery processes are used. Crystallisation from a solvent is the most common nondistUlation method for the purification of these alkylphenols. [Pg.64]

Most commercially important alkylphenol production is of three types, unrefined alkylphenols, mono alkylphenols, and dialkylphenols. Together, these processes comprise over 95% of all alkylphenol production in the United States. The boundaries between types of production are not rigid and some commercially important production is through a combination of these processes. [Pg.64]

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. [Pg.244]

Di- and Triisobutylcncs. Diisobutylene [18923-87-0] and tnisobutylenes are prepared by heating the sulfuric acid extract of isobutylene from a separation process to about 90°C. A 90% yield containing 80% dimers and 20% trimers results. Use centers on the dimer, CgH, a mixture of 2,4,4-trimethylpentene-1 and -2. Most of the dimer-trimer mixture is added to the gasoline pool as an octane improver. The balance is used for alkylation of phenols to yield octylphenol, which in turn is ethoxylated or condensed with formaldehyde. The water-soluble ethoxylated phenols are used as surface-active agents in textiles, paints, caulks, and sealants (see Alkylphenols). [Pg.372]

Snia Viscosa. Catalytic air oxidation of toluene gives benzoic acid (qv) in ca 90% yield. The benzoic acid is hydrogenated over a palladium catalyst to cyclohexanecarboxyhc acid [98-89-5]. This is converted directiy to cmde caprolactam by nitrosation with nitrosylsulfuric acid, which is produced by conventional absorption of NO in oleum. Normally, the reaction mass is neutralized with ammonia to form 4 kg ammonium sulfate per kilogram of caprolactam (16). In a no-sulfate version of the process, the reaction mass is diluted with water and is extracted with an alkylphenol solvent. The aqueous phase is decomposed by thermal means for recovery of sulfur dioxide, which is recycled (17). The basic process chemistry is as follows ... [Pg.430]

The sheer complexity of environmental mixtnres of EDCs, possible interactive effects, and capacity of some EDCs to bioaccumulate (e.g., in fish, steroidal estrogens and alkylphenolic chemicals have been shown to be concentrated up to 40,000-fold in the bile [Larsson et al. 1999 Gibson et al. 2005]) raises questions about the adequacy of the risk assessment process and safety margins established for EDCs. There is little question that considerable further work is needed to generate a realistic pictnre of the mixture effects and exposure threats of EDCs to wildlife populations than has been derived from studies on individual EDCs. Further discussion of the toxicity of mixtures will be found in Chapter 2, Section 2.6. [Pg.284]

FD-MS is also an effective analytical method for direct analysis of many rubber and plastic additives. Lattimer and Welch [113,114] showed that FD-MS gives excellent molecular ion spectra for a variety of polymer additives, including rubber accelerators (dithiocar-bamates, guanidines, benzothiazyl, and thiuram derivatives), antioxidants (hindered phenols, aromatic amines), p-phcnylenediamine-based antiozonants, processing oils and phthalate plasticisers. Alkylphenol ethoxylate surfactants have been characterised by FD-MS [115]. Jack-son et al. [116] analysed some plastic additives (hindered phenol AOs and benzotriazole UVA) by FD-MS. Reaction products of a p-phenylenediaminc antiozonant and d.v-9-lricoscnc (a model olefin) were assessed by FD-MS [117],... [Pg.375]

The aim of this review is to present a comprehensive evaluation of the presence of three classes of emerging contaminants in sludge alkylphenols, hormones, and pharmaceuticals. In particular, the fate of these compounds during sewage and sludge treatment by aerobic and anaerobic processes is addressed. [Pg.73]

In the negative FIA-MS spectra, the sulfate, phosphate and carboxylate of these anionic alkylphenol ether derivatives in parallel to the aliphatic ethoxy surfactants show equally spaced signals with Am/z 44. However, according to the ionisation method applied—APCI or ESI in the negative or positive mode—and also that observed in the ionisation process of AES, equally spaced signals came either from the anionic compounds themselves or from the alkylphenol ethers... [Pg.352]


See other pages where Alkylphenols processes is mentioned: [Pg.83]    [Pg.540]    [Pg.30]    [Pg.107]    [Pg.285]    [Pg.286]    [Pg.292]    [Pg.190]    [Pg.247]    [Pg.362]    [Pg.514]    [Pg.78]    [Pg.81]    [Pg.121]    [Pg.56]    [Pg.72]    [Pg.684]    [Pg.748]    [Pg.794]    [Pg.957]    [Pg.491]    [Pg.403]    [Pg.94]    [Pg.95]    [Pg.3]    [Pg.69]    [Pg.110]    [Pg.83]   
See also in sourсe #XX -- [ Pg.52 , Pg.59 ]




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Alkylphenol

Alkylphenols

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