| Abstract: | Activated carbon was used for the treatment of waste water, and a study made of the fixing-properties of the adsorbent and the part played by micro-organisms. The process of “fixing” remains to be demonstrated because it has not yet been proved that bacteria are fixed on carbon. Study of the biological mechanism of activated carbon was carried out in three stages. The first was a survey of the adsorption on this material of various products present in waste water [amino-acids, enzymes, total organic matter (COD)]. In the course of these tests, the part played by the micro-porosity of activated carbon in regard to such molecules was observed. In the second stage, by using various techniques (electron microscope, scanning and transmission, X-ray fluorescence, Castaing micro-gauge), we determined the part played by fixation-spots initially present on carbon (surface functions, heavy metals) during bacterial development. In the third stage, we correlated the eliminated organic pollution with the bacterial mass present on the adsorbing material.The conclusions drawn were that the micro-porosity of carbon does not play a fundamental part in the adsorption of organic matter in sewage, but it does come into play in the adsorption of certain molecules taken separately (amino-acids, enzymes), and that the presence of fixation-spots (metals, surface functions) can have some influence during bacterial development. Experiments are in progress to determine the part played by the specific surface in regard to the adsorbable molecules and its correlation with the bacterial mass and also, to observe the part played the adsorbing material and the bacteria in regard to the non-adsorbable molecules (ethanol, methanol). |
