NOPR Collection:

Fly ash – A cheap Catalyst in wet oxidation of an industrial pesticide effluent

Wed, 01 Feb 1995 00:00:00 GMT

Title: Fly ash – A cheap Catalyst in wet oxidation of an industrial pesticide effluent Authors: Pramanik, S; Sur, B; Dutta, B K; Chaudhuri, S K Abstract: Fly ash, a solid waste from thermal power plants, has been used as a catalyst in reduction of COD of an industrial pesticide effluent by wet oxidation with H₂O₂at different temperatures. It has been found that 10% (w/v) fly ash loading enhanced the percent reduction of COD from 28.72 to 88.73 for a H₂O₂ loading of 4.5% at 335 K. The catalytic effect of fly ash remains unchanged even after fifth repeated use and more than 94% of the oxygen librated from H₂O₂is consumed for COD reduction. The spent fly ash exhibit good pozzolanic reaction, which suggests a potential route of utilization of spent materal. Page(s): 44-47

Effect of calcination parameters of alumina hydrate on the properties of alumina

Wed, 01 Feb 1995 00:00:00 GMT

Title: Effect of calcination parameters of alumina hydrate on the properties of alumina Authors: Patnaik, S C; Satapathy, B K; Pradhan, B Abstract: In the present investigation, the variation of properties of alumina hydrate and alumina during calcination with respect to different parameters like temperature, retention time, grain size and soda content to evaluate the change of BET surface area have been studied. The effect of mineralisers like AIF₃ and NH₄F, for transformation of alpha phase of alumina has also been studied on a laboratory scale. Coversion to about 96% of alpha alumina was achieved by using 1% of mineraliser at 1100ᵒ C. While the BET surface area reduced with temperature and finner size of alumina hydrate, the alpha formation showed an increasing trend. The change of properties like density, porosity, humidity and compressibility with respect to temperature has also been reported. Page(s): 40-43

Novolac epoxy resin based inhibition system for composite propellants

Wed, 01 Feb 1995 00:00:00 GMT

Title: Novolac epoxy resin based inhibition system for composite propellants Authors: Agrawal, J P; Gholap, D H; Bansod, V P; Agawane, N T Abstract: Thirty one compositions based on commercially available Dobeckot E4, polyamide hardener EH411, polyamine hardener 758, reactive diluent, Dobeckot C and antimony trioxide filler have been made and studied in terms of characteristics such as gel time, exotherm peak temperature, tensile strength, elongation, burning rate, loss in weight, water absorption and bond strength with composite propellants. Based on important characteristics, composition 28 has been selected for inhibition of composite propellants (booster and sustainer mode) and statically evaluated after conditioning at ambient temperature (+27^oC for 24 h), cold (- 40^o C for 20 h) and hot (+ 50^oC for 16 h). The P-t profiles show that the composition 28 is a potential inhibition system for composite propellants from -40 to + 50^oC. Page(s): 34-39

Infuence of heat treatment parameters on the microstructure and tensile behaviour of an austempered ductile iron containing 1.4Ni and 0.6Mo

Wed, 01 Feb 1995 00:00:00 GMT

Title: Infuence of heat treatment parameters on the microstructure and tensile behaviour of an austempered ductile iron containing 1.4Ni and 0.6Mo Authors: Rao, P Prasad Abstract: The effect of processing parameters such as austenitinsing time and tempratute and austempering temperature on the microstructure and mechanical properties of a ductile iron containing 1.4 wt% nickel and 0.6 wt% molybdenum has been studied. It was found that there was extensive carbide precipitation at higher austempering temperatures leading to loss of strength as well as ductility. Strength was found to be higher at lower austenitising temperatures. Lower austenitising time and temperature was also found to promote higher carbide precipitation during austempering. Page(s): 24-33