Theoretical and experimental studies of isothiazolinone adsorption onto ordered mesoporous silica

SANDRA SIMONETTI; MARÍA SOLEDAD LEGNOVERDE; LUCAS EMANUEL MARDONES; ELENA ISABEL BASALDELLA

Rio de janeiro

Conferencia; 18th International Zeolite Conference; 2016

International Zeolie Association y Brazilian Catalysis Society

IntroductionMethylisothiazolinone/chloromethylisothiazolinone (MIT/CMIT) are the active ingredients in a family of commercial microbiocides and preservatives that have a broad spectrum of activity against fungi, yeasts and both gram-positive and gram-negative bacteria1. These biocides are prone to leaching under humid conditions owing to their high water solubility, resulting in the increased concentrations required during initial processing, but their enlarged use may not be economically or environmentally acceptable. These active ingredients could be microencapsulated to solve this problem. This methodology is generally used to increase the protection of the active compounds from the surrounding environment, to control their release rate into the medium, or a combination of both.In the present study, SBA-15 materials were used as matrices for the encapsulation and stabilization of an MIT/CMIT mixture. The main objective of this work was to demonstrate the effective location of the biocide inside the silica pores and to verify that the biocide molecules remain unaltered (retain their structure) after adsorption. To do this, the biocide location was determined by registering the changes in the textural properties of the support during the adsorption process, and the molecular integrity of the adsorbed biocide was determined by FTIR. The possible interactions of MIT/CMIT with SBA-15 were also modeled using a theoretical approach.