| The oily waste water from marine oil spills is one of the culprits that endangers the safety of marine life and destroys the balance of marine ecology.In addition,oil spills can have adverse effects on human health,the climate and even the living environment.In addition,with the expansion of industry and urbanisation,a large amount of industrial and domestic wastewater has been discharged,which has aggravated the environmental problems of oily wastewater.For a long time,the treatment of oily waste water has attracted much attention in national scientific research.In addition to incineration and microbial decomposition,artificial separation is a more favourable method,which can not only reduce secondary pollution,but also enable the recovery of spilled oil.With the development of the theoretical basis of polymer science and processing technology,polymer sponges have played an important role in the manufacture of oil/water separation materials.Compared with other polymer sponges,melamine sponge（MS）is considered to be more suitable for oil/water separation process due to its higher porosity,flame retardancy and mechanical properties.However,commercially available MS has a water/oil amphiphilic property,which greatly limits its application in practice,so hydrophobic modification of it is essential.According to super-wetting theory,hierarchical surface structure and low surface free energy are two necessary conditions for the preparation of superhydrophobic materials.In most cases,surface roughness can be improved by loading nano/micron particles on the material surface,while to reduce the surface free energy compounds containing fluorine elements or long chain alkanes are usually used.This thesis explores the use of molybdenum disulfide（Mo S2）modification for superhydrophobic modification of commercial MS based on super-wetting theory,with the following two parts of the study.The surface modification of molybdenum sulfide（Mo S2）using dopamine（PDA）and octadecyltrimethoxysilane was firstly performed to obtain superhydrophobic Mo S2@Si O2-C18H37 particles,and then the superhydrophobic modification of MS was achieved by loading the superhydrophobic Mo S2@Si O2-C18H37 particles onto a commercial MS skeleton by coating impregnation.During the preparation process,the epoxy resin（EP）cross-linked with the curing agent can fix Mo S2@Si O2-C18H37 on the sponge surface,which will form a rough structure on the skeleton and reduce the surface energy.Further results show that the resulting superhydrophobic MS has the best hydrophobicity with a water contact angle（WCA）of 151.5°at an impregnating solution concentration of 0.06 g/m L and can maintain stable hydrophobicity under complex environments.The oil/water separation test showed that the composite sponge still had good selective adsorption ability for various oil/water mixtures after 50 cycles.In addition,the MS/EP/Mo S2@Si O2-C18H37 sponge has excellent continuous separation capability and can be used for oil/water separation processes under a variety of conditions.The MS/EP/Mo S2@Si O2-C18H37 prepared by the above method has excellent hydrophobicity and separation ability,but its maximum adsorption capacity is limited by the preparation method and the epoxy resin coating closes the vesicular structure of the sponge during the curing process.Therefore,the second part of the work focuses on improving the adsorption capacity of superhydrophobic MS.The superhydrophobic modification of Mo S2 using tannic acid（TA）and octadecylamine（ODA）was firstly used to obtain Mo S2@ODA particles.Then the solution impregnation method was used to load Mo S2@ODA onto the MS surface,and finally the MS@（Mo S2@ODA）sponge was obtained.The WCA test results showed that when the impregnation solution concentration was 0.015 g/m L,the sponge had the best hydrophobicity,and its was156.2°,which was 4.7°higher than that of MS/EP/Mo S2@Si O2-C18H37.Similarly,the hydrophobicity of the MS@（Mo S2@ODA）sponge was able to maintain stability under complex environments.Due to the avoidance of EP coating in the preparation process,the MS vesicular structure is preserved intact and the sponge weight gain is reduced.As a result,the maximum adsorption capacity can reach 145.7 times of its own mass,which is much higher than the maximum adsorption capacity of the superhydrophobic MS prepared in the previous section.Further tests showed that MS@（Mo S2@ODA）also has excellent recyclability and continuous separation capability. |
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