Alternating copolymerization of carbon monoxide with ethylene or 1-olefins in aqueous emulsion by water-insoluble palladium(II) complexes is reported. Latices of aliphatic polyketones (1-olefin/CO copolymers and ethylene/undec-10-enoic acid/CO terpolymers), prepared by catalytic polymerization, are described for the first time. An in situ catalyst system [{R2P (CH2)-) were used in the form of a solution of the palladium(II) complex in miniemulsion droplets of a hydrocarbon dispersed in the continuous aqueous phase. Catalyst activities of up to 5 × 10 3 TO h -1 slightly exceed those of nonaqueous polymerizations in methanol with the same catalysts. Polymer molecular weights (GPC vs PMMA standards) are typically Mw 2 × 10 5 (ethylene copolymers) respectively Mw 2 × 10 4 (1-olefin copolymers) with Mw/Mn 2-4. The 1-olefin copolymers exhibit glass transition temperatures of Tg ) +10 to -55°C, which is in the range desirable for latex applications.

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A simple analytical procedure is proposed for simultaneous determination of three common dyes (Basic Blue 9, Brilliant Blue E-4BA, and Reactive Blue 2) in natural waters without prior separation of the solutes. A popular chemometric method, partial least squares regression PLS-1, was effectively applied for spectral resolution of a highly overlapping system. At the best modeling conditions, mean recoveries and relative standard deviations (RSD) for dyes quantification by PLS-1 were found to be 102.1 (4.4), 95.7 (8.4), and 98.9 (6.2) for Basic Blue, Brilliant Blue, and Reactive Blue, respectively. The estimated limits of detection (LOD) were estimated using net-analyte signal concept and were 0.11, 0.52, 0.49 mg L(-1) for Basic Blue, Brilliant Blue, and Reactive Blue, respectively. The quantitative determination of dyes spiked in real water samples was carried out successfully by PLS-1 with satisfactory recoveries for dyes (90-106%).

With a total concentration of 7055 mgS/kgfuel, the content of organosulphur compounds (OSCs) in local diesel is 20 times higher than the regulated value. Analysis revealed that 30% of OSC is originated from dibenzothiophene (DBT). It is known that DBT is a hardly removable compound and selective adsorbents are often needed for its removal with low affinity for other diesel components. In this work, a selective adsorbent based on surface modification of activated carbon (AC) by MnO2 is prepared for DBT removal from diesel. The porous nature of AC enabled carrying large amounts of MnO2 particles to end up with a selective adsorber for DBT. The best performance was observed at a surface loading of 26.8% of Mn and DBT is favourably removed over mono- and diaromatics hydrocarbons in diesel. Adsorption kinetics of DBT is studied under a high initial concentration of 835-11,890 mg/kg and at a ratio of 11 cm3/g (diesel:carbon). The results indicated a fast removal process after surface modification where 96% of the surface is occupied within 30 min of interaction. Kinetic data were best presented by reaction-based models with low prediction error sum of squares values 0.5-47.0, while, diffusion-based models showed limited application for modelling DBT adsorption. Accordingly, adsorption process is controlled by surface reactions and pore diffusion has a minor role in the overall process. The modified adsorbent is satisfactorily regenerated using n-hexane at 65°C.

Water‐soluble palladium complexes cis‐[Pd(L)(OAc)2] (1–8) (L represents a diphosphine ligands of the general formula CH2(CH2PR2)2, where for a: R  (CH2)6OH; b–g: R  (CH2)nP(O)(OEt)2, n = 2–6 and n = 8; h: R  (CH2)3NH2) have been employed, after activation with a large excess of HBF4, for emulsion polymerization of alkenes (propene, butene, and their equimolar mixtures) with carbon monoxide. Aliphatic polyketone lattices with a high solid content (21%), high molecular weight (6.3 × 104 g mol−1), and narrow polydispersities (Mw/Mn ≈ 2) were isolated. The catalytic activity of the dicationic palladium (II) based catalysts, C1–C8 is highly dependent on the length of the alkyl chain of the ligand. Catalyst 3 proved to be highly active for propene/CO copolymers, whereas 6 is active for butene/CO and propene/CO‐butene/CO systems. The presence of methyl β‐cyclodextrin, as a phase‐transfer agent, and undecenoic acid, as an emulsifier, increase the molar mass and the stability of the polyketones and finally the activity of the catalyst. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6715–6725, 2009