Since caffeine is soluble into water, we are able to decaffeinate coffee through several different processes. A few very common methods use the saturation of water and introduction of Methylene Chloride or Ethyl Acetate. These chemicals bind the caffeine and allow it to evaporate. The traces allowable by the FDA of these chemicals are only 10 parts per million but most end up at about 1 parts per million. However there are methods that use water to remove the caffeine called the Swiss Water Method. This method uses carbon filters to remove the caffeine once it is in the water the beans are soaked in. This method is certified organic and uses no chemicals. All in all, the process usually takes about 10 hours in most cases.