Reductive dechlorination of trichloroethylene by polyvinylpyrrolidone stabilized nanoscale zerovalent iron particles with Ni

Abstract We developed a novel stabilized nanoscale zerovalent iron (NZVI) particles with Ni using an electron conducting polymer, polyvinylpyrrolidone (PVP), to selectively dechlorinate trichloroethylene (TCE) to non-toxic intermediates. The size of the PVP stabilized NZVI-Ni ((PVP-NZVI-Ni), average diameter: ∼20nm) is smaller than that of bare NZVI (50–80nm) due to the prevention of agglomeration of the resultant iron particles by PVP. PVP-NZVI-Ni showed a complete removal of TCE in 1h with superior dechlorination kinetics (kobs=5.702h−1) and ethane selectivity (98%), while NZVI-Ni showed 5 times slower dechlorination kinetics (1.218h−1). Other PVP-NZVI-metals (i.e., Cu, Sn, Co, and Mn) also enhanced the TCE dechlorination, but they were much slower (kobs=0.024−0.411h−1) than that of PVP-NZVI-Ni. In column test, PVP-NZVI-Ni exhibited better mobility (95% of PVP-NZVI-Ni recovery in the eluent) than NZVI-Ni (1%). In addition, PVP-NZVI-Ni reductively transform TCE to ethane even under 10 cycles of repeated TCE dechlorination treatment

Reductive dechlorination of trichloroethylene by polyvinylpyrrolidone stabilized nanoscale zerovalent iron particles with Ni

We developed a novel stabilized nanoscale zerovalent iron (NZVI) particles with Ni using an electron conducting polymer, polyvinylpyrrolidone (PVP), to selectively dechlorinate trichloroethylene (TCE) to non-toxic intermediates. The size of the PVP stabilized NZVI-Ni ((PVP-NZVI-Ni), average diameter: similar to 20nm) is smaller than that of bare NZVI (50-80nm) due to the prevention of agglomeration of the resultant iron particles by PVP. PVP-NZVI-Ni showed a complete removal of TCE in 1 h with superior dechlorination kinetics (k(obs) =5.702 h(-1)) and ethane selectivity (98%), while NZVI-Ni showed 5 times slower dechlorination kinetics (1.218 h(-1)). Other PVP-NZVI-metals (i.e., Cu, Sn, Co, and Mn) also enhanced the TCE dechlorination, but they were much slower (k(obs) =0.024-0.411 h(-1)) than that of PVP-NZVI-Ni. In column test, PVP-NZVI-Ni exhibited better mobility (95% of PVP-NZVI-Ni recovery in the eluent) than NZVI-Ni (1%). In addition, PVP-NZVI-Ni reductively transform TCE to ethane even under 10 cycles of repeated TCE dechlorination treatment. (C) 2017 Elsevier B.V. All rights reserved.116sciescopu

Catalyst-free synthesis of amines from cyclic ketones and formamides in superheated water

<p>A novel and environmentally benign protocol for the synthesis of amines from cyclic ketones and formamides is demonstrated. The reaction proceeds under catalyst-free and superheated water conditions and yields range from poor to excellent.</p

Regio- and stereoselective co-iodination of olefins using NH₄I and Oxone

<p>A simple, efficient, and environmentally benign protocol for the synthesis of vicinal iodohydrins and iodoesters from olefins using NH₄I and Oxone in CH₃CN/H₂O (1:1) and dimethylformamide (DMF) / dimethylacetamide (DMA), respectively, without employing a catalyst at room temperature is described. Regio- and stereoselective iodohydroxylation and iodoesterification of various olefins with <i>anti</i> fashion, following Markonikov’s rule, was achieved and the corresponding products were obtained in good to excellent yields. In addition, 1,2-disubstituted olefins afforded excellent diastereoselectivity.</p