Адсорбционное извлечение аминов из водных растворов

В статических условиях изучена возможность очистки водных растворов, содержащих экстрагенты - первичный амин (Primene-JMT) и третичный амин (триоктиламин, ТОА), адсорбцией на углеродных материалах (активированном угле NWC, угле NWC-T, модифицированном углеродными нанотрубками, угле УС-ПТФЭ, модифицированном политетрафторэтиленом), а также на стиролдивинилбензольном неионогенном сополимере Поролас-Т и природном адсорбенте - ракушечнике. Методом ограниченного объёма раствора изучена кинетика адсорбции аминов Primene-JMT и ТОА из водных растворов этими адсорбентами. Из известных моделей псевдо-первого порядка, псевдо-второго порядка и Еловича модель псевдо-второго порядка более адекватно описывает кинетические данные (R2>0,99). Определены значения коэффициентов распределения и констант скорости адсорбции аминов Primene-JMT и ТОА. Предложена блок-схема адсорбционной очистки водных растворов от экстрагентов, реализация которой позволит снизить токсичность сбросных растворов и вернуть в оборот часть дорогостоящего экстрагента.

Aquatic biological resources are an important part of the ecosystems of our planet, since they are involved in economic turnover as a source of food. The composition of water, including waste water from enterprises, has a direct impact on the state of aquatic biological resources. To extract and concentrate metals from solutions, hydrometallurgical processes are used - extraction and sorption. Their implementation is possible with the use of special substances - extractants and in a number of processes - sorption materials (Solvent Impregnated Resins (SIR’s) and Levextrel’s) with a mobile phase of the extractant, combining the properties of sorbents and extractants. Despite the advantages of the latter, such as high kinetic parameters, lack of swelling and high values of mechanical strength, they are characterized by the disadvantages of extraction methods - the entrainment of the extractant into the aqueous phase in dissolved and emulsion forms. Under static conditions, the possibility of purification of aqueous solutions containing primary or tertiary amine by adsorption on carbon materials (activated carbon NWC, carbon NWC-T modified with carbon nanotubes, CS-PTFE modified with polytetrafluoroethylene), as well as on styrene-divinylbenzene nonionic copolymer Porolas-T and a natural shell rock adsorbent was studied. The kinetics of adsorption of аmines Primene-JMT and TOA from aqueous solutions by these adsorbents has been studied by the method of a limited volume of solution. Of the known pseudo-first order, pseudo-second order and Elovich models, the pseudo-second order model describes kinetic data more adequately (R2>0.99). The values of the distribution coefficients and the rate constants of adsorption of Primene-JMT and TOA are determined. A block diagram of adsorption purification of aqueous solutions from amines is proposed, the implementation of which will reduce the toxicity of waste solutions and return some of the expensive extractant to circulation.