Study On The Removal Of Organic Acid Using Ion-exchange Resin During The Production Of Fuel Ethanol

Fuel ethanol is a kind of renewable resource. It is widely used, therefore, it has an important significance as it can save the petroleum resource, lower environmental pollution and promote grain transformation. Acidity is one of the most important indexes of fuel ethanol. Acidity of fuel ethanol is related to organic acid in the fuel ethanol. The more concentrated the organic acid is, the higher the acidity will be. Acetic acid is the main component affecting acidity of fuel ethanol.A new approach of using ion-exchange resin to remove the organic acid formed in the production process of fuel ethanol and in the end product was applied. It resolved the negative effects of the product use and process effluent disposal, which were caused by adding sodium hydrate to control the acidity of ethanol in the traditional ethanol production process. This approach enables the removal of organic acid in fuel ethanol process to have a cleaner production.The 330 resin was chosen using static adsorption, dynamic adsorption and elution to remove the organic acid in the fuel ethanol process.Using solution, which makes up of acetic acid and ethanol, as the study object, the influences of temperature, concentration and flow on the adsorption were studied. Its optimum adsorption conditions were determined that flux was 6.37BV/h and temperature was at 30℃. An the same time, through elution experiment, its optimum elution conditions were determined that concentration of sodium hydroxide solution was 4%, flux was 3.18BV/h and temperature was at 30℃.The adsorption isotherm was measured using batch adsorption equilibrium between acetic acid in the ethanol and resin. The adsorption isotherm is according to the Langmuir model on the basis of all correlation coefficients over 0.99.Using dynamic adsorption experimental apparatus, on the condition of that the bed temperature is at 30℃and the solution fluent is 6.37BV/h, the breakthrough curve was measured. And through the breakthrough curve, the model of mass transfer zone on adsorption fixed bed was gotten.Adopting 330 resin in the optimum adsorption condition of removing organic acid in the fuel ethanol, it deals well with the unqualified fuel ethanol, which is caused by the high acidity formed during the industrial production.The study on the removal of organic acid using ion-exchange resin during the production of fuel ethanol is instructive not only to the fuel ethanol process, but also to the edible ethanol process. This technique has prospective application.