| In dealing with oil spills at sea,the oil-absorbing material was widely used because they can concentrate and retain oil.Environmental friendly oil-absorbing materials have larger adsorption capacity and low price,and they can be easily used and would not produce secondary pollution.Environmental friendly oil-absorbing materials can make oil recycled and avoid new environmental problems,and they have broad application prospects.Therefore,the search for environment-friendly oil-absorbing materials.and carry out the applied research has a great practical significance.In this paper,we selected clay material(modified organobentonite,diatomaceous earth,Na-bentonite) and exfoliate graphite and studied Adsorption of pollutants on the performance of diesel.The adsorption kinetics,adsorption isotherm were studied and to explore the adsorption mechanism.By orthogonal on the adsorption conditions were optimized.By comparing the number of adsorption equilibrium adsorption capacity, price and ease of follow-up,made a reasonable implementation.This experiment using UV spectrophotometric determination of oil content of seawater through the test produced the following major conclusions:1.Through the adsorption kinetics experiment,secondary absorption kinetic equation of modified organobentonite,exfoliate graphite,diatomaceous earth and Na-bentonite are established.The equilibrium adsorption capacity of modified organobentonite,exfoliate graphite,diatomaceous earth and Na-bentonite is 3271,3078,1525 and 1212 mg/g respectively,and equilibrium time is 15.18,18.92 36.15 and 48.39 min respectively.2.Oil removal efficiency increased with the increase of adsorbing material added in the system,and decreased with the increase of original oil content in seawater,in the scope of the study in the experiment,the modified organobentonite,exfoliate graphite,diatomaceous earth and Na-bentonite in seawater with the oil removal rate are increased with temperature,salinity and oscillation frequency.3.With the oil pollution of seawater pH values increase,exfoliate graphite,diatomaceous earth and Na-bentonite in the oil removal rate has decreased;and the modified organobentonite in the pH value of 8,the removal can be achieved better results. 4.The adsorption isotherms of modified organobentonite and diatomaceous earth can be described as Freundlich's equation.The adsorption isotherms of exfoliate graphite and Na-bentonite can be used Langmuir isotherm and Freundlich isotherm to describe,The Langmuir isotherm is more appropriate.5.Modified organobentonite absorption of oil,primarily through inter-layer organic phase,which plays a role in distribution;The absorption mechanism of exfoiiate graphite are surface absorption and oil-filled space absorption,of which spaces fill accounted for one of the main part;The adsorption mechanism of diatomaceous earth are mainly microporous coordination absorption and surface adsorption:Na-bentonite including the absorption mechanism of the surface absorption and the role of organic matter distribution.Thermodynamic calculations of modified organobentonite,exfoliate graphite,diatomaceous earth and Na-bentonite on the adsorption of diesel oil is physical adsorption.6.The impact of modified organobentonite for oil adsorption followed by the main factors:salinity＞pH＞oscillation frequency＞temperature.The impact of exfoliate gaphite for oil adsorption followed by the main factors:temperature＞oscillation frequency＞salinity＞pH.The impact of diatomaceous earth for oil adsorption followed by the main factors:pH＞salinity＞temperature＞oscillation frequency.The impact of Na-bentonite for oil adsorption followed by the main factors: pH＞salinity＞temperature＞oscillation frequency.7.Comparison of the effect of oil-absorbing materials,oil,technology economy and ease of follow-up treatment.Consider the four types of oil-absorbing materials.modidied organobentonite has most advantages and potential in practical application..it is more suitable for the treatment of sea spills. |
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