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Sewage sludge (SS) incineration technology has become a primary method to recover and reuse SS, and the cocombustion with coal is a more feasible process due to the limited heating value of wet SS and the difficulty of drying SS. Being that phosphorus is a major element in SS, its migration during cocombustion with coal was unclear but vital. Phosphorus migration during the cocombustion of wet SS and various coals was investigated by drop tube furnace in this study. More phosphorus was fixed as apatite in ash by calcic and magnesian minerals at 1000 °C than at 800–900 °C. Calcium was taken up by sulfur in Tianchi coal (TC) and subsequently captured phosphorus ineffectively at 800 °C, while the competition of sulfur on calcium was alleviated over 900 °C. Silicic and aluminic minerals in Xiheishan coal (XHS) exhibited a good capacity for phosphorus capture at 800 °C. The outstanding calcic proportion in Xiaolongtan coal (XLT) created the highest rate of phosphorus fixation in ash, and the relative enrichment (RE) of phosphorus achieved up to 93.29% at 1000 °C. Steam generally deteriorated phosphorus capture at 1000 °C. For SS cocombustion with XHS, the effect of sulfur was alleviated by steam, and the impact of steam was mainly caused by Ca5(PO4)3OH. For SS cocombustion with TC or XLT, 10% steam still hindered phosphorus capture, while 5% steam promoted phosphorus capture. The RE of phosphorus in ash was positively correlated with coal content and increased from 69.64% with 30% XLT to 93.29% with 70% XLT. TC and XHS hindered phosphorus fixation in ash, and their content hardly affected the RE of phosphorus.

The chiral diiminodiphosphine ligand, [(R,R)-P2N2], has been prepared by the condensation of o-(diphenylphosphino)benzaldehyde and 1,2-diaminocyclohexane. [(R,R)-P2N2] was reduced with excess NaBH4 in refluxing ethanol to afford the corresponding diaminodiphosphine ligand [(R,R)-P-2(NH)(2)]. The interaction of [(R,R)-P-2(NH)(2]) With trans-RuCl2(DMSO)(4) gave the chiral ruthenium complex [(R,R)-RuP2(NH)(2)] in 84% yield. The reaction of [(R,R)-RuP2(NH)(2]) With Poly(acrylic acid) using dicyclohexylcarbodiimine as the coupling agent, gave water soluble poly(acrylic acid salt)-supported chiral ruthenium complex [PAA-(R,R)-RuP2(NH)(2)]. These chiral ligands and ruthenium complexes have been fully characterized by microanalysis and IR, NMR spectroscopic methods. The polymer-bound ruthenium complex [PAA-(R,R)-RuP2(NH)(2)] as catalyst was used in asymmetric transfer hydrogenation of acetophenone in 2-propanol, producing the 1-phenyl-ethanol in 95% yield and 96% ee. The catalyst was reused twice with some loss of activity and enantioselectivity. Copyright (C) 2001 John Wiley Sons, Ltd

Sewage sludge (SS) contained considerable phosphorous resource and SS incineration technology had become an important method to reuse SS. To alleviate the difficulty of SS mono-combustion caused by its low heating value, high-rank fuels should be introduced. Effects of SS and coal co-combustion on phosphorus fixation rate in ash were studied through drop tube furnace. It was concluded that rising temperature increased the fixation rate of phosphorus in SS ash. Due to the obvious high calcium content in Xiaolongtan coal (XLT), the co-combustion of SS and XLT effectively increased the fixation rate of phosphorus in ash and phosphorous capture by solid minerals was improved by temperature increase. In the meanwhile, more XLT introduced more calcium into the combustion system, which captured more phosphorous in ash. Whereas, there were just a small quantity of calcic and magnesian minerals in Xiheishan coal (XHS) and as a result, higher temperature accelerated phosphorous emission. The fixation rate of phosphorus during co-combustion of SS and XHS was not significantly affected by the different proportions of XHS. Finally, the co-combustion of 70 % XLT and 30 % SS effectively fixed phosphorus at 1000 °C, where the fixation rate in ash was risen dramatically to as high as 93.29 %.