Synthesis Of Superwetting Materials And Their Application In Oil And Water Separation

Massive oil spills and organic wastewater discharges pose a great risk to the natural environment and human health.Therefore,researchers urgently need an effective method to solve this problem.Because of the special selection of wettability,extreme wetting materials provide a good way for people to solve this problem.In recent years,superwetting materials,represented by super hydrophobic materials,have made great achievements in the field of oil-water separation and greatly promoted its development.Inspired by nature,two key factors for the preparation of extreme wetting materials are the construction of rough structure at the micro/nano scale and the modification of low surface energy materials,which complement each other.With the continuous in-depth research on extreme wetting materials,a series of products have been used for water purification and oil-containing wastewater treatment,which greatly facilitate our life.However,with the continuous improvement of demand,some deficiencies have been exposed,such as high production cost,complex process and environmental unfriendly problems.Therefore,the use of simple process,cheap raw materials,green process to prepare the properties of stable,efficient separation of oil and water mixture of extreme wetting materials for practical application and environmental protection has a vital significance.In this paper,the cheap and easily available magnesium oxide and iron tetroxide are used as the main raw materials,and the fabric and sponge are modified by common low surface energy modifier.The main research contents of this paper are as follows:(1)Using magnesium oxide particles and aluminate,a stable super hydrophobic fabric with oil-water separation and bearing capacity has been successfully prepared.The tape stripping test,folding test,washing test and pH test show that the modified fabric has good stability.Especially,when the fabric is loaded with a weight of 200 g it can move up to 22 m on 600#sandpaper without losing its superhydrophobicity.The fabric can withstand pressure in water of 66.8 N/m2,with good water bearing capacity.The superhydrophobic and superoil-wet property can be used to separate oil and water in different oil-water mixtures,the separation efficiency is over 90%,which proves that the material has excellent oil-water separation ability.The superhydrophobic fabric has certain application value in the fields of sewage purification and diving equipment.(2)A green,fluorine-free,durable and low-cost superhydrophobic magnetic sponge was successfully prepared from Fe3O4 particles and stearic acid.It can be controlled by changing the magnetic field to avoid the operator’s direct contact with toxic and harmful solvents,which is an advantage that traditional oil-water separation materials do not have.The prepared materials can be soaked for 7 days under the harsh conditions of acid solution,alkali solution and salt solution,and still remain superhydrophobic.In the extrusion deformation test with loading weight of 200 g and 80 cycles(compression strain of 75%),the superhydrophobicity is still found,which proves that the material has good chemical stability and mechanical stability.The sponge can be used for the separation of oil-water mixture and the purification of oil-water emulsion.It is worth mentioning that this material can separate and purify the crude oil emulsion,which is rarely studied.Magnetic superhydrophobic sponge can be prepared in large scale by simple and easy method.These results provide a way for the effective utilization of sponge and show its potential application prospects in oil-water separation,sewage purification,emulsion purification and oil spill collection.