Glucose removal from water mixtures at concentrations ranging from 40 to 0.15 w/w%, via CO2 hydrates formation and separated melting

Abstract

Similarly to ice, gas hydrates can be used to purify water from contaminants. The removal efficiency depends of several parameters, such as the chemical composition of the contaminant, its geometry and size, its charge and others. The process was tested for water mixtures containing glucose at different concentrations, ranging from 40 to 0.15 w/w%. To process meaningful quantities of water, the production of hydrates must be abundant. Therefore, CO₂ hydrates were formed at seven different concentrations within the previously mentioned range. Only the concentrations corresponding to the best performances were selected to carry out experiments finalized at defining the removal efficiency of the process. For this second scope, hydrates were formed again, separated from the remaining liquid phase and then melted. The obtained water was analysed and the concentration of glucose measured. The comparison between the initial and the final concentrations, allowed to define the overall feasibility of the process.