NOPR Community:

Liquid-liquid extraction of thorium(IV) with binary mixture of PC88A and TOPO from aqueous HCIO₄ media

2016-07-20T05:58:39Z

Title: Liquid-liquid extraction of thorium(IV) with binary mixture of PC88A and TOPO from aqueous HCIO₄ media Authors: Mishra, Sujata; Chakravortty, Y Abstract: The extraction of thorium(IV) with PC88A is very high from low HCIO₄ concentration. It gradually decreases with increase in acidity. The addition of synergist TOPO to PC88A in kerosene improves the extraction of thorium(IV) from 0.2-1.6 M HCIO₄ solution. The study with different diluents shows maximum distribution ratios obtained in case of kerosene. Page(s): 373-374

A comparative evaluation of cephalosporin -C production in stirred tank reactor and air lift reactor

2016-07-20T05:57:36Z

Title: A comparative evaluation of cephalosporin -C production in stirred tank reactor and air lift reactor Authors: Srivastava, Pradeep; Nigam, V K; Kundu, Subir Abstract: Cephalosporins group of antibiotics are more resistant to β lactamases than penicillins and are produced from cephalosporin - C (CPC), which is exclusively produced by fermentations. Many strains are used for the production of CPC. However, Cephalosporium acremonium is widely used because of its high yield The CPC production is a highly aerobic process. Sucrose was found to be the most suitable substrate at 30 g/L. The CPC production has been studied in 2.0 L stirred tank reactor (STR) and 1.4 L air lift reactor (ALR), and performance compared, using a working volume 1.0 L. The maximum specific growth rate was 0.045 and 0.037 h^-1 in STR and ALR respectively. The maximum cell mass concentrations were 685 mg L^-1 in ALBR and 780 mg L^-1 in STR. The specific antibiotic productivity based on power input (CPC/(P/ V) is higher by a factor of 2.4 in ALR than in STR. Page(s): 371-372

Solvent extraction separation of Cu(II) and Ni(II) with bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex 301)

2016-07-20T05:56:41Z

Title: Solvent extraction separation of Cu(II) and Ni(II) with bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex 301) Authors: Shinde, Priyadarshini S; Dhadke, P M Abstract: The extraction behaviour of copper(II) and nickel(lI) with bis(2,4,4-trimethyl pentyl)dithiophosphinic acid has been studied at various parameters such as, pH, acidity, reagent concentration, equilibration period, solvent effect and effect of diverse ions. The copper(II) was quantitatively extracted from 0.5 MHCI with 5 x 10^-3 M Cyanex 301 and nickel(II) was extracted at pH 8.00 with 5 x 10^-3 MCyanex 301. The brownish yellow copper complex absorbed at 440 nm while coloured complex of nickel showed maximum absorption at 340 nm. Both metals were separated from multicomponent mixtures. The proposed method was successfully employed for the determination of copper and nickel in real samples. Page(s): 367-370

Solvent extraction separation of molybdenum(VI) with dibenzo 18-Crown-6 from chloride solutions

2016-07-20T05:55:28Z

Title: Solvent extraction separation of molybdenum(VI) with dibenzo 18-Crown-6 from chloride solutions Authors: Rane, Sneha S; Khopkar, S M Abstract: Molybdenum(Vl) was quantitatively extracted with 0.01 M dibenzo 18-Crown-6 (DB18C6) in dichloroethane from 3-8 M hydrochloric acid, and was stripped with 0.05 M hydrochloric acid. After dryashing it was determined spectrophotometrically as its complex with Tiron at 390 nm. Other crown ethers such as 15C5, DC18C6 and DB24C8 were ineffective for extraction but with DB18C6 the extraction was quantitative. Amongst diluents only dichloroethane was effective. The stripping was complete with dilute solutions (0.05 M) of hydrochloric acid. Molybdenum(Vl) was separated from large number of elements with which it is generally associated in minerals. The method was extended for analysis of molybdenum in real samples. The relative standard deviation was ± 1.2%. Page(s): 363-366

NOPR Community:

Liquid-liquid extraction of thorium(IV) with binary mixture of PC88A and TOPO from aqueous HCIO4 media

A comparative evaluation of cephalosporin -C production in stirred tank reactor and air lift reactor

Solvent extraction separation of Cu(II) and Ni(II) with bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex 301)

Solvent extraction separation of molybdenum(VI) with dibenzo 18-Crown-6 from chloride solutions

Liquid-liquid extraction of thorium(IV) with binary mixture of PC88A and TOPO from aqueous HCIO₄ media