Influence of Ionic Liquid 1- butyl-3-methylimidazolium Chloride on the Soil Micro-Ecological System

Abstract

In order to evaluate the influence of ionic liquid 1- butyl-3-methylimidazolium chloride ([Bmim]Cl) on the soil micro-ecological system, the toxicity of [Bmim]Cl to soil microorganisms and its impact on soil physico-chemical properties were investigated. Three soil samples, which were taken from the rape land, nursery land and the broad bean land respectively, were used for this study. The toxicity test results show that the [Bmim]Cl inhibited the growth of soil microorganisms including bacteria and actinomycetes. This inhibition became stronger with the [Bmim]Cl concentration increasing. The EC50 of soil bacteria was close to that of the Vibrio fischeri , and the EC50 of soil actinomycetes was near to that of the Pseudokirchneriella subcapitata . The soil physico-chemical properties test results indicate that the organic mass and the soluble salts in soil increased with the increase of the [Bmim]Cl concentration. The [Bmim]Cl also caused the pH change in the soil micro-ecological system. It suggests that the ionic liquid [Bmim]Cl would influence the soil micro- ecological system by inhibiting the growth of soil microorganisms and altering the soil physico-chemical properties when it contaminated the soil system.