Investigations of physical chemistry processes related with the binding of environmental relevant heavy metal ions by calix[4]arenes using molecular dynamics simulations

Abstract

The consequences of human activities to the environment are becoming disturbing in the last decades. In particular, subjects related with the conservation of world drinking water supplies are present in the schedule of the most important meetings of world leaders. In this context we can highlight the problem of water pollution by heavy metals originated from mining activities, unappropriated discard of batteries, gasoline burn, etc. The calixarenes are macrocyclic molecules with the property to bind, selectively, different heavy metal ions depending on their chemical composition. Thus, these molecules are natural candidates to be used in the development of products for environmental cleanse. Despite the vast material already published about this subject, specially in experimental areas, the details of the physical chemistry processes involved in the binding of ions by calixarenes are far from be completely understood. The use of computer simulations to investigate this kind of system can be very useful, since with this technique it is possible to follow the system's dynamic behavior at atomic/molecular level and from this results to obtain relevant informations and conclusions. In this project we propose the study, using Molecular Dynamic simulations, of physical chemical processes related with the bind of Pb2+, Cd2+, Hg2+ e Ag+ ions by four calixarenes: Tetramethylketone p-tert-butyl calix[4]arene (CLC), Tetraethylester p-tert-butyl calix[4]arene (CLE), Diethylsulfoxy p-tert-butyl calix[4]arene (CLS) e Diethylester diethylsulfoxy p-tert-butyl calix[4]arene (CLS/E). The objective is to get insights about physical chemistry properties of these systems not yet completely understood, contributing with the rational calixarene design research area. (AU)