NOPR Collection:

A new catenary-type equation for the bubble-point temperature and bubble-point pressure of binary solutions

Mon, 01 Mar 1999 00:00:00 GMT

Title: A new catenary-type equation for the bubble-point temperature and bubble-point pressure of binary solutions Authors: Wisniak, Jaime; Segura, Hugo Abstract: A new empirical equation is proposed for the correlation of the boiling points of a binary solution. The equation contains three adjustable parameters and predicts very well the experimental values of the bubble-point temperature and bubble- point pressure. Page(s): 57-62

Adsorption of basic dyes from aqueous solution by natural adsorbent

Mon, 01 Mar 1999 00:00:00 GMT

Title: Adsorption of basic dyes from aqueous solution by natural adsorbent Authors: Khattri, S D; Singh, M K Abstract: The capability of the Sagaun sawdust for removing basic dyes (crystal violet, methylene blue, malachite green and rhodamine B) from aqueous solutions has been investigated. The effect of system variables such as concentration, temperature, pH and particle size have been studied to understand equilibrium and kinetics of adsorption process. The maximum removal was found to be 89% at concentration 6.0 mgL^-1, temperature 30⁰C and pH 7.5 . The amount of the dye(crystal violet and methylene blue) adsorbed, decreases from 2.773 mg g^-1 (86.68%) to 2.310 mg g^-1 (72.19%) and 2.672 mg g^-1 (83.52%) to 2.205 mg g^-1 (68.93%) with the rise of temperature of dye solutions from 25 to 45⁰C indicating the process to be exothermic. The value of k_ad of crystal violet at 25 , 35 and 45⁰C were found to be 9.72x10^{- 2}, 9.57x 10^-2 and 9.25x10^-2 min^-1 ,respectively. The adsorption capacity for dye-adsorbent system has been determined. The dye adsorption follows the Langmuir isotherm. On the basis of isotherm studies, various thermodynamic parameters such as ΔG⁰, ΔH⁰ and ΔS⁰ have been calculated. Page(s): 112-116

Residence time distribution of solids in a fluidised bed

Mon, 01 Mar 1999 00:00:00 GMT

Title: Residence time distribution of solids in a fluidised bed Authors: Chapadgaonkar, Samir S; Setty, Y Pydi Abstract: The present work involves an experimental investigation on residence time distribution of solids in a continuous fluidised bed for uniform size and for binary solid mixture at different dilutions. The column was tested for improvement in performance with increase in dilution. The effect of gas flow rate, solids flow rate and dilution on the first, second and third moments and on F-curves have been determined. Fractional tank extension model fits the experimental data. High values of N as dilution increases, indicates reduced solids mixing, thus reducing spread of residence times, giving rise to more uniform quality of product. The work finds importance in that similar improved performance of the column using internals inside the bed can be obtained by using a mixture of solids rather than uniform size. Page(s): 100-106

Corrosion inhibition of copper in aqueous chloride solution by diphenyl amine and cupric diphenyl dithiocarbamate

Mon, 01 Mar 1999 00:00:00 GMT

Title: Corrosion inhibition of copper in aqueous chloride solution by diphenyl amine and cupric diphenyl dithiocarbamate Authors: Singh, M M; Rastogi, R B; Upadhyay, B N; Yadav, M Abstract: The inhibition of copper corrosion in 1.5% sodium chloride solution was studied in the presence of different concentrations of diphenyl amine and its Cu(II) diphenyl dithiocarbamate complex . Both the compounds act as good corrosion inhibitors for copper. Their inhibitive action has been compared with those of diethyl analogues and contrary to the theoretical expectations these inhibitors have been found to exhibit lower inhibition efficiencies. Page(s): 93-99