NOPR Collection:

Process monitoring of Dibenz-[b,f]-1 ,4-Oxazepine (CR) by gas chromatographic method

2016-07-20T06:26:18Z

Title: Process monitoring of Dibenz-[b,f]-1 ,4-Oxazepine (CR) by gas chromatographic method Authors: Bag, Bidhan Chandra; Kaushik, M P Abstract: Dibenz (b,f)-1,4-oxazepine (CR) is a new nontoxic skin irritant and is very useful as a riot control agent. A simple, specific and rapid Gas Chromatographic method with flame ionization detection for the determination of CR and its precursors and the process monitoring of the CR production is described. After a concise sample preparation, samples were injected on Gas Chromatograph (GC) column at 200°C for o-chlorobenzaldehyde (OCB) and 250°C for CR. In monitoring the process it was observed that in the first reaction 96.6% OCB was converted to Schiff's base (SB) within 25 min and 75% of potassium salt so formed by the reaction of SB with methanolic potassium hydroxide was converted into CR in 160 min. Repeatability of the described gas chromatographic method was evaluated by analyzing five replicates of the samples of OCB, SB and CR. Page(s): 415-419

Synthesis and analytical application of lead selective thorium iodate cation exchanger

2016-07-20T06:27:33Z

Title: Synthesis and analytical application of lead selective thorium iodate cation exchanger Authors: Kunhikrishnan, M Jitha; Janardanan, C Abstract: A new inorganic ion exchanger thorium iodate was synthesized and characterized by studying the properties like ion exchange capacity, pH titration curves, distribution coefficients for various metal ions, effect of hydrated ionic radii, temperature, electrolyte concentration, etc. on the ion exchange capacity. The empirical formula proposed for the ion exchanger is ThO₂.I₂O₅.nH₂O. Important binary as well as ternary separations were carried out. The synthetic utility of the exchanger is revealed from the separation studies. The separation performed on the ion exchanger column is very important for the environmentalists, since the mixtures analysed are Cu²⁺-Pb²⁺, Ni ²⁺-Pb²⁺,Cd²⁺-Pb²⁺ and Hg²⁺-Pb²⁺. Page(s): 420-423

Pb₃BrF₅: A lead halo composite as catalyst for allylation reactions

2016-07-20T06:30:13Z

Title: Pb₃BrF₅: A lead halo composite as catalyst for allylation reactions Authors: Raj, N K Kala; Sajanikumari, C S; Unni, I R; Halligudi, S B; Gopinathan, C Abstract: The solid lead halo composite Pb₃BrF₅, has been found to be an active reagent in the allylation of anisole, phenol and diphenyl ether (dpe). This catalyst favoured the formation of monoallylated products with all the three substrates, showing higher selectivity for para isomers. Side products of allylation of phenol were allyl phenyl ether and 1,3-bis (2-hydroxy phenyl) propane, and for anisole and dpe, their respective diallylated products. The lead halo composite adsorbs HBr (formed in the reaction) and prevents the occurrence of consecutive reactions. Page(s): 411-414

Effect of temperature on pitting corrosion of 316 SS in concentrated phosphoric acid containing hydrochloric acid

2016-07-20T06:27:32Z

Title: Effect of temperature on pitting corrosion of 316 SS in concentrated phosphoric acid containing hydrochloric acid Authors: Singh, M M; Khare, Rita; Mukherjee, A K Abstract: Anodic polarization experiments were conducted on AISI 316 SS in 14 M H₃PO_4, containing 0-0.55 M of HCl at 298, 308 and 318 K. The anodic parameters i_c, i_p, E_pp, E_p and E_b were determined from the anodic polarization curves. It was found that both critical current density, i_c and passivity current density, i_p increased with rise in temperature. The parameters E_pp, E_p and E_b attained more active values with rise in temperature within the range of HCl concentrations investigated. Potential decay experiments were carried out to determine the characteristics of the passive films formed on 316 SS, which were found to be temperature dependent - their porosity increasing with rise in temperature. The pitting potential, E_pit and protection potential, E_pr were determined for various HCl concentrations using the reverse polarization technique. Page(s): 407-410

NOPR Collection:

Process monitoring of Dibenz-[b,f]-1 ,4-Oxazepine (CR) by gas chromatographic method

Synthesis and analytical application of lead selective thorium iodate cation exchanger

Pb3BrF5: A lead halo composite as catalyst for allylation reactions

Effect of temperature on pitting corrosion of 316 SS in concentrated phosphoric acid containing hydrochloric acid

Pb₃BrF₅: A lead halo composite as catalyst for allylation reactions