Medyanik N.L.

The right choice of surface active substances significantly predetermines the efficiency of ionic flotation and therefore development of a plausible method to evaluate the properties of the reagents is an important task with regard to industrial realisation of the process.

Scientifically justified selection of reagents considering their quantum chemical properties, development of algorithms of their application provides efficiency and accuracy of the actions of selectors, stability of qualitative-quantitative data of the flotation process, reduction of the flotation reagent’s losses at cleaning sewerage waters in hydrometallurgical plants.

Technogenic waters contain heavy metals ions displaying electrophilic properties; therefore for their extraction nucleophilic reagents are necessary. The calculation of quantum chemical parameters has shown that the compositions comprising the reagents have the large values of maximal negative charges concentrated in heteroatoms. The molecules have relatively high energetic values of the energy of highest occupied molecular orbital (HOMO) and molecular electric negative charges giving credence to stiff nucleophilic characters (Table).

Quantum Chemical Properties of Reagent Molecules

The authors for flotation extraction of heavy metals ions offered the reagent ROL produced by utilization of polyethylene terephtalat wastes. The compositions compounding the reagent ROL have nucleophilic character than compositions traditionally used reagents for sewage water cleaning. The performed flotation trials confirmed the possibility of selecting effective reagents for ionic flotation with the use of quantum-chemical calculations.

The use of the ROL reagent leads to higher extraction of heavy metals ions by 50 - 55% compared to conventional collectors. According to the requirements for collectors employed by ionic flotation the ROL reagent is a regular solute since it is diluted in a weak-pole solvent – ethylenglycol fully mixed with water; in small amounts it is indifferent to the process, during storage does not produce micelle, has a foam building and high surface activity. The use of new reagent is feasible from economic and ecological point of view, as ROL reagent can be produced through utilization of worn polyethilentereftalat package, which should improve ecological situation in cities.