SOLVENT EXTRACTION OF LANTHANIDES WITH N-m-AND N-p-METHOXYBENZOYL-N-PHENYLHYDROXYLAMINE

The solvent extraction of lanthanides with N-o-methoxy-(o-MBPHA), N-m-methoxy- (m-MBPHA) and N-p-methoxybenzoyl-N-phenylhydroxylamine (p-MBPHA), respectively, in chloroform was studied. The selected lanthanides (Yb, Ho, Eu, Pr and La) were all found extract with m- and p-MBPHA as self-adducts of the form LnL-2HL, where L and HL denote the ligand anion and neutral ligand, respectively. The extraction constant and separation factors for the lanthanides with m- and p-MBPHA were evaluated.     

THIRD PHASE FORMATION IN EXTRACTION OF THORIUM NITRATE BY MIXTURES OF TRIALKYL PHOSPHATES

ABSTRACT

This paper reports the results of the studies on third phase formation during the extraction of thorium nitrate from zero free acidity solutions by mixtures of trialkyl phosphates. The phosphates used are tri n-butyl phosphate(TBP), triiso butyl phosphate(TiBP), tri sec butyl phosphate (TsBP) and tri n-amyl phosphate(TAP). The results indicate that small additions of a homologous phosphate can alter the Limiting Organic Concentration (LOC) above which the third phase formation takes place and thus can be advantageously utilised. Use of mixtures of the trialkyl phosphates as extractant can thus obviate the need for adding modifiers such as alcohols to the organic phase for avoiding third phase formation.     

DRYING CHARACTERISTICS OF TAPIOKA

Experimcntal studies were carried out on a multipurposc industrial solar drycr having corrugated absorber with two glass covers. Drying charactcristics of Tapioka wcre obtained on the fixed bed portion of this dryer