Study On Chemical Modification,Characterization And Oil Absorption Of Wheat Straw

With the development of oil exploration and development on the sea and land,the petroleum processing industry is rising day by day,and the problem of oil spill is becoming more and more serious.In the process of exploitation,transportation and use of oil,nearly 1million tons of oil enters the water environment in the world every year due to improper discharge,spilling and transportation leakage and so on.The resulting water pollution,soil pollution,serious damage to the ecological environment,but also damage to the healthy development of mankind.In the face of pollution caused by petroleum,the follow-up process is to apply various methods to comprehensively control the ecological crisis and minimize the ecological crisis.In this paper,two kinds of high efficient oil-absorbing materials,AWS and Fe₃O₄/RWS were prepared by esterification and surface loading modification with wheat straw powder as substrate.The materials before and after modification were characterized by scanning electron microscope,Fourier transform infrared spectroscopy and X-ray diffraction.The oil absorption properties of the modified materials were studied.The following conclusions are drawn:1)For AWS,the optimum preparation conditions were as follows:acetic anhydride solution 40ml,NBS and PWS were 0.5g and 2g respectively,reaction temperature was 100?and reaction time was 1.5 h.2)For Fe₃O₄/RWS,the optimum preparation conditions were as follows:RWS and ethylene glycol,ferric chloride hexahydrate,sodium citrate,sodium acetate and polyethylene glycol respectively at the ratio of 1g 40 ml 0.4 g 0.15g 1.8g 1g,when the filling degree of the solution in the reactor was 80%for 12h at 220?.3)For AWS,the results show that the surface of the modified material loses its original smooth structure,becomes rough and burr,has a lot of irregular folds.The obvious weakening of the hydroxyl characteristic peak in infrared spectrum and the absorption peak of the new ester functional group show that the esterification is successful.The decrease of crystallinity in XRD diffraction pattern also shows that the crystalline structure of straw cellulose is destroyed.For the composite oil-absorbing material Fe₃O₄/RWS,the results showed that a layer of nano-ferromagnetic particles with good dispersion was deposited on the surface and internal pore size of wheat straw.The contact angle test results showed that the composite had excellent hydrophobicity,which directly confirmed that the nano-ferromagnetic particles prepared by solvothermal method had strong oil solubility and lipophilicity.4)The results showed that the oil absorption of RWS PWS AWS and Fe₃O₄/RWS were8.84g/g and 17.4g/g respectively at room temperature.The results showed that the oil absorption properties of the modified materials increased greatly,and the modified materials had excellent hydrophobic and floating properties.Fe₃O₄/RWS has excellent hydrophilic hydrophobicity at the same time.The material can be easily recovered by applying magnetic field.Therefore,the two oil-absorbing materials have profound research and application value in oil pollution control.