NOPR Collection:

Impact of brass and electroplating industry effluent on some physicochemical and biological properties of soil

2008-06-06T06:35:26Z

Title: Impact of brass and electroplating industry effluent on some physicochemical and biological properties of soil Authors: Saraswat, Shweta; Tewari, Saumyata; Rai, J P N Abstract: A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain, where soil was irrigated by toxic metal rich brass and electroplating industrial effluent in suburban area of Moradabad, India. Spatial and seasonal variations of total heavy metal content in soil and their effect on physico-chemical and biological properties were studied in soil samples taken from 0-25, 25-50 and 50-75 cm soil depth. Except pH, all parameters were maximum in summer in surface soil at each site. Total metal content decreased with increasing distance from the effluent course. Physico-chemical values (pH, EC, Corg, available N etc.) were found minimum at S1 and maximum at S3. Significant inhibition of microbial biomass C and N, respiration, dehydrogenase activity and microbial coefficient occurred in soils highly contaminated by heavy metals. There was a significant decrease in Cmic/Nmic ratio and an increase in metabolic quotient (qCO₂) with increasing metal concentration. Page(s): 957-962

Kinetic characterization of removal of As (III) by mixed adsorbents

2008-06-06T06:35:23Z

Title: Kinetic characterization of removal of As (III) by mixed adsorbents Authors: Singh, A P; Srivastava, K K; Shekhar, H Abstract: Adsorption kinetics for removal of arsenic was carried out by red mud and its mixtures with haematite, china clay and fly ash besides china clay-fly ash at: adsorbate conc., 5.0 mg1-1; particle size of adsorbent, <53 μm; agitation rate, 220 rpm; pH, 8.0; and temp., 30, 40 & 50°C. Data fit into Lagergren equation and adsorption follows first order reaction kinetics. As(III) removal by adsorbents is diffusion controlled. A low value of activation energy indicates flat nature of energy barrier. Page(s): 952-956

Sorption and ion exchange behavior of Pb(II), Bi(III) and Th(IV) in aqueous solutions towards zirconium phosphate

2010-07-14T16:30:09Z

Title: Sorption and ion exchange behavior of Pb(II), Bi(III) and Th(IV) in aqueous solutions towards zirconium phosphate Authors: Jayswal, Amit; Chudasama, Uma Abstract: Amorphous zirconium phosphate (ZP), an inorganic ion exchanger of the class of tetravalent metal acid (TMA) salt, has been synthesized by sol-gel method, and characterized by elemental analysis (ICP-AES), thermal analysis (TGA, DSC), FT-IR and X-ray diffraction studies. Sorption/ion exchange behavior of metal ions [Pb(II), Bi(III) and Th(IV)] towards ZP has been studied varying temperature, kinetic (over all rate constant k2 and equilibrium constant kc,) and thermodynamic parameters (standard free energy ΔG°, enthalpy ΔH°, and entropy ΔS°) evaluated and adsorption isotherms (Langmuir and Fruendlich) studied. Sorption of metal ions follows the order Pb(II) > Bi(III) > Th(IV). Page(s): 945-951

Use of waste plastics and copper slag for low cost bituminous roads

2008-06-06T04:30:42Z

Title: Use of waste plastics and copper slag for low cost bituminous roads Authors: Kajal; Pundhir, N K S; Sangita; Chandra, A Abstract: Study presents use of waste plastics and copper slag (CS) in hot bituminous mixes to enhance pavement performance, protect environment and provide low cost roads. Waste plastic modified bitumen (WPMB) has been prepared by adding mixed plastic waste (5%) in shredded form with suitable cross-linking agent in 80/100 bitumen and blended for 1 h at 160°C. Physical properties of WPMB are found within specified limits (IS: 15462-2004). Delhi quartzite aggregate (size, 20 mm, 10 mm), stone dust and lime along with varying concentrations of CS as aggregate filler is taken for preparation of Marshall specimens (60/70 paving bitumen, 80/100 paving bitumen and WPMB). Optimum binder content is achieved at 5.2% (by wt of mix). Marshall specimens are also prepared with composition of CS (10, 15 and 20%) replacing stone dust; CS (15%) has been found best. Page(s): 938-944