Preparation Of Expanded Graphite And Its Absorbing Properties For Oil In Waste Water

In recent years, the frequent oil spilling incidents of the oil tanker and the blindness draining of the industrial oily waste water have caused serious pollution to the surroundings. To solve this problem, many scholars at home and abroad have been trying to explore the feasibility of using new carbonaceous sorbent, especially the expanded graphite for adsorbing oil in waste water. However, the adsorption mechanism and the main factors affecting the adsorption process are still not clear, so more efforts are needed for the application research.The chemical intercalation method was adopted and the natural flake graphite, concentrated sulfuric acid and chemical oxidants were used as the starting materials. By changing the concentration of the intercalation sorbent, the concentration and type of chemical oxidant, reaction time and other parameters, the influence on the pore structure of the expanded graphite was studied, and excellent expanded graphite with large porous volume was produced. By studying the basic adsorption properties and adsorption mechanism, the influence of the physical and chemical properties, the expanded graphite structure, and the oil's physical and chemical properties on its adsorption behavior were introduced. Besides, the focus was shifted from the static adsorption in the laboratory to the oilfield for a dynamic adsorption experiment. It was found that wrapping space and the pore structure between the carbon layers can be controlled by adjusting the packing density, therefore, both the large suspended oil and the small emulsified oil particles can be adsorbed separately.China is rich in graphite; the production is ranked first in the world, so the raw materials used in this study are cheap and readily available. The oil industry which consumes large amount of water brings even larger amount of waste water containing oil. China is relatively short of water, so the reuse of the industrial waste water has become an imperative of saving measures. The high water content in the oilfield is a unique situation in our country. The recycling of the oil field and refinery wastewater or pouring back to underground after advanced treatment would have very good economic and social benefits.