| Adsorption and separation materials are considered to be the most effective way to solve the problem of oil slick cleaning in water,oily wastewater purification and organic matter removal in water.The preparation and research of oil-water separation materials is currently an important direction to solve environmental pollution and resource waste.In this paper,three kinds of oil-water separation materials were prepared for different forms of oil pollutants,which provide new ideas and methods for solving the problem of environmental oil pollution and the research and development of new oil-water separation materials.The use of waste polyacrylonitrile fiber（WPAN）as the raw material had solved the problem of resource shortage and waste to a certain extent.It was truly low-carbon and environmentally friendly,and it had huge social and economic benefits.The main work was divided into three parts.The details were as follows:1.For slick oil or dispersed oil pollutants,the polyacrylonitrile oil-absorbing material（POAM）was prepared used WPAN as raw materials through silane coupling agent KH-550treatment and low-temperature oxidation method.In the experiment,the oil absorption rate and water contact angle were used as indicators to evaluate the oil absorption performance of samples,and engine oil was used as the adsorption object.The optimum preparation parameters:the concentration of KH-550 was 0.05%,the immersion time was 50 min,and the oxidation temperature was 280℃.Subsequently,the sample’s microscopic morphology,surface functional groups,hydrophobic and lipophilicity,adsorption performance for different oils and organic solvents,oil retention performance,chemical stability and reusability were characterized or tested.The results show that POAM had hydrophobic and super lipophilic properties,and the contact angles of pure water and engine oil were 142.2°and 0°,respectively.The adsorption capacity of different oils or organic solvents reached 16.02-47.26times of its own weight.It has been found to have excellent oil retention properties,while being resistant to chemical corrosion such as acids and salts.After ten adsorption-squeezing cycle experiments,the adsorption performance of the oil-absorbing material was still relatively stable.2.In order to further increase the oil adsorption capacity of the oil absorbing material,the reduced graphene oxide（RGO）was choosed as the reinforcing phase and the WPAN still were used as raw materials.The PAN/RGO composite material was prepared by a combination of hydrothermal reaction and freeze-drying method.The optimum preparation parameters were determined:the mass ratio of PAN to GO was 10:3,the mass ratio of GO to L-AA was 1:1,the hydrothermal temperature was 80℃,and the hydrothermal time was 7 h.The results show that the contact angles of the composite to pure water and engine oil were134.8° and 0°,respectively.The adsorption capacity of different oils or organic solvents reached 42.8-177.2 times of its own weight.Utilizing its hydrophobic and lipophilic properties,it realized the separation of oil slick or dispersed oil and water.At the same time,it had an excellent oil retention effect of 96.8%,and had strong resistance to chemical corrosion such as strong acid and high salt.After ten cycles of testing,the adsorption efficiency remained at about 90%of the initial adsorption capacity.3.In order to remove the emulsified oil or dissolved oil in the sewage,we prepared a polyacrylonitrile microfiltration membrane（AT-PAN-MM）by the L-S phase inversion method.The optimum preparation parameters were determined:the film thickness was 100μm,the PAN concentration was 7%,and the alkali treatment time was 1 h.The experimental results show that AT-PAN-MM had super hydrophilicity and super low underwater oil adhesion.It can be applied to the effective separation of oil-water emulsions in the presence of different kinds of surfactants.The membrane fluxes all exceed 1290 L·m-2·h-1·Bar-1,and the rejection rates are all greater than 99%. |
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