Alkylbenzene derivative

In activated sludge, 80.6% degraded after a 47-h time period (Pal et al., 1980). Chemical/Physical. Zhang and Rusling (1993) evaluated the bicontinuous microemulsion of surfactant/oil/water as a medium for the dechlorination of polychlorinated biphenyls by electrochemical catalytic reduction. The microemulsion (20 mL) contained didodecyldi-methylammonium bromide, dodecane, and water at 21, 57, and 22 wt %, respectively. The catalyst used was zinc phthalocyanine (2.5 nM). When PCB-1221 (72 mg), the emulsion and catalyst were subjected to a current of mA/cm on 11.2 cm lead electrode for 10 h, a dechlorination yield of 99% was achieved. Reaction products included a monochlorobiphenyl (0.9 mg), biphenyl, and reduced alkylbenzene derivatives. 

Electron-transfer reactions are normally performed in polar solvents such as acetonitrile (MeCN), in which the product ions of the electron transfer are stabilized by the strong solvation [6,7]. When a cationic electron acceptor (A ) is employed in electron-transfer reactions with a neutral electron donor (D), the electron transfer from D to A+ produces a radical cation (D +) and a neutral radical (A ). In such a case, the solvation before and after the electron transfer may be largely canceled out when the free-energy change of electron transfer is expected to be rather independent of the solvent polarity. The solvent independent value is confirmed by determination of the Eqx values of alkylbenzene derivatives (electron donors) and Ered values of acridinium cations (electron acceptors) in solvents with different polarities [79]. The E°ox values of alkylbenzene derivatives in a less polar solvent (CH2CI2) are shifted to the positive direction by about 0.1 V... 

Zhang and Rusling [66] employed a stable, conductive, bicontinuous microemulsion of surfactant/oil/water as a medium for catalytic dechlorination of PCBs at about 1 mA cm-2 on Pb cathodes. The major products were biphenyl and its reduced alkylbenzene derivatives, which are much less toxic than PCBs. Zinc phthalocyanine provided better catalysis than nickel phthalocyanine tetrasulfonate. The current efficiency was about 20% for 4,4 -DCB and about 40% for the most heavily chlorinated PCB mixture. A nearly complete dechlorination of 100 mg of Aroclor 1260 with 60% Cl was achieved in 18 hr. Electrochemical dehalogenation was thus shown to be feasible in water-based surfactant media, providing a lower-cost, safer alternative to toxic organic solvents. 

When alkylbenzene derivatives are submitted to metallation, the metal may displace either a benzylic (a) or a ring hydrogen atom (preferably at the sterically unhindered meta or para positions). To avoid contamination by the ring-metallated derivative, a-deprotonation of toluene needs to be done with Schlosser s base18 191,192 while, for example, TMEDA-activated butyllithium gives rise to some contamination by ring-metallated products.193,194 Examples of mono- and dimetallation of alkylbenzenes are reported in Table 8. 

Zmierczak et al.4 have investigated the catalytic hydrocracking of non-vulcanized rubber (SBR, styrene-butadiene copolymers) over superacid solids, consisting of sulfated Zr and Fe oxides. Figure 6.7 shows the GC-MS analysis of the liquids produced at 400 °C over sulfated Fe203, with assignments of the main peaks. Three types of product are observed C5-C9 paraffins produced from the butadiene blocks of the polymer, alkylbenzenes derived from the... 

In contrast to TPS with its branched alkyl chain, n-dodecylbenzene sulfonate exhibits an extremely fast rate of biodegradability. The change-over from a branched to a straight-chain structure is easily achieved, and thus by the use of Ziegler synthesis and molecular-sieve extraction techniques, industrial processes for the production of linear olefines and -alkanes soon became readily available. These are the basic starting materials for the synthesis of linear alkylbenzene derivatives. 

We have found that the alkylbenzene derivatives with no hydrogen atom in benzyl positions can act as a mediator to decompose carbonate solvents, as postulated in Fig. 4.20, because they showed a reversible redox reaction and increased the amount of evolved CO without losing themselves. A terf-butylbenzene and 1,3-di-tert-butylbenzene showed lower OCVs compared with toluene, ethylbenzene, and cumene after the overcharge test at 60°C, as shown in Fig. 4.21, which is a good indication as an overcharge protection agent. 

Production of alkylbenzene derivatives in the 1940 s was linked to the Fischer-Tropsch synthesis. In 1941, IG Farbenindustrie began to produce chloroparaffins by chlorination of a Fischer-Tropsch alkane mixture rich in n-paraffins with an average chain length of C14 the chloroparaffin was made to react with benzene under Friedel-Crafts conditions and subsequently sulfonated to yield an alkylbenzene sulfonate. The product was given the trade name Tgepal NA . 

Since linear alkylbenzene derivatives are more readily biodegradable than branched ones, the use of branch-chain alkylbenzene sulfonates has sharply declined with the introduction of respective regulations since the mid-1960 s (e.g. the West German Detergents Law of 1962). 

The possibilities of following more complicated kinetic systems at RDE are documented in two examples. The first deals with the oxidation of alkylbenzene derivatives mediated by ruthenium complexes [66]. The following reaction scheme has been assumed the generation of the mediator - ruthenium(III) bipyridine complex - at the electrode... 

Chang, C.-L. and H.S. Fogler Stabilization of Asphaltenes in Aliphatic Solvents Using Alkylbenzene-Derived Amphiphiles. 1. Effect of the Chemical Structure of Amphiphiles on Asphaltene Stabilization, Langmuir, vol. 10, p. 1749,1994a. 

Mtlller, K., D. Noffz, Length and the degree of branching of the alkyl chains of surface-active alkylbenzene derivatives (in German), Tenside, 1965,2,68-75. 

Argentation TLC was used to separate alkylbenzenes derived from LAS (21). Silica gel plates impregnated with silver nitrate were used with a developing reagent of hexane and visualization with 2,7-dichlorofluorescein. Although the main purpose of the separation was isolation of alkylbenzenes as a group, it was observed that individual isomers are separated from each other. 

---