The Preparation And Performance Study Of Nano Composite Pour Point Depressant For Waxy Crude Oil

Na-montmorillonite was organically modified at first and modification effect was tested and characterized.Nanocomposite pour point depressant was prepared.Then rheological behavior at low temperature of Hongde oil added traditional pour point depressant and nanocomposite pour point depressant were researched by contrast experiments.Furthermore,the function mechanism of nanocomposite pour point depressant on waxy crude oil is discussed.Montmorillonite was organically modified by quaternary ammonium salt.Modification effect was tested by Fourier transform infrared spectrometer,scanning transmission electron microscope and X-radial Diffractometer.The results show that the montmorillonite layers structure was inserted into long chain alkyl of octadecyl trimethyl ammonium chloride which is cationic surfactants.Sheet layers was reduced,distance between lamellas was enlarged.The solubility of montmorillonite in organic solvent is increased.Nanocomposite pour point depressants of different types and different proportion were prepared by using of a polymer solution intercalation method.Rheological behavior of Hongde oil which was added with traditional pour point depressant and nanocomposite pour point depressant were researched by using AR-G2 type rheometer,differential scanning calorimeter and solidifying point measuring device.Experimental results show that there is an optimal ratio and optimal additive dosage of nanocomposite pour point depressants;Wax precipitation temperature of Hongde oil has not changed with adding Nanocomposite pour point depressants;compared with traditional pour point depressant,under the same conditions additives,pour point and viscosity can be further reduced;yield value at low temperatures is significantly reduced.The Nanocomposite pour point depressant also has a better characteristics in anti-repeated heating and static stability.The structure of waxy crystal of Hongde oil was observed by polarizing microscope.Microscope images show that wax crystal was separated and gathered with montmorillonite as the carrier to form a globular structure which was larger,denser and more regular boundary.Wax crystals become more dispersed,it is difficult for waxy to overlap each other to form a space network structure which results in better effects.