▎ 摘　　要

NOVELTY - Magnetic nano fiber demulsifier comprises ferric oxide nanoparticles as the inner layer, the magnetic graphene oxide nanocomposite as the middle layer, and the nonionic surfactant as the outer layer. The demulsifier is in the form of fibers prepared by the electrospinning method of ferric oxide nanoparticles, magnetic graphene oxide nanocomposites and nonionic surfactants. USE - The magnetic nano fiber demulsifier is useful for low-temperature gathering and transportation of crude oil used in oil and gas field exploitation. ADVANTAGE - The magnetic nano fiber demulsifier can keep very high dehydration rate under the condition of repeated use to improve the demulsification efficacy under the conditions of obviously reducing the energy consumption. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing magnetic nano fiber demulsifier, comprising (i) adding oxygen-deionized deionized water into a flask with nitrogen atmosphere, heating it to a certain temperature T1 between 65 and 75degrees Celsius, maintaining it at a constant temperature, stirring, adding ferrous chloride tetrahydrate and ferric chloride hexahydrate successively into deoxygenated deionized water to obtain a ferric ion mixture, stirring the ferric ion mixture in a constant temperature T1 and a nitrogen atmosphere, adding sodium hydroxide solution dropwise into the ferric ion mixture, using the ferric ion mixture for preparing ferric oxide nanoparticles is stirred to obtain the precipitation of ferric oxide nanoparticles in a constant temperature T1 and a nitrogen atmosphere, separating the ferric oxide nanoparticles by filtration, washing fully with deoxygenated deionized water, and drying the ferric oxide nanoparticles for 3-8 hours at any temperature between 75degrees Celsius and 85degrees Celsius in a vacuum drying oven to prepare ferric oxide nanoparticles; (ii) loading the concentrated sulfuric acid into the reaction flask, placing the reaction flask in the cold bath of the cooling medium, stirring, adding graphite into obtain a mixed system of concentrated sulfuric acid and graphite, adding potassium permanganate slowly into the mixed system while stirring, maintaining the temperature of the system not higher than 20degrees Celsius, placing the mixed system obtained in an oil bath with a temperature of 35-40degrees Celsius for 10-50 minutes, adding slowly deionized water into the mixed system under stirring until the temperature of the heated to 95-100degrees Celsius, stirring continuously for a period of time, mixing the hydrogen peroxide and deionized water in the mixed system, removing excess unreacted manganese oxide when observing system color changes from dark brown to yellow to obtain product graphene oxide, washing the resulting graphene oxide fully with dilute hydrochloric acid and deionized water successively to remove any unreacted residual materials, and drying in a vacuum drying oven at 50-70degrees Celsius for 3-8 hours to prepare graphene oxide; (iii) stirring deionized water by adding ferric oxide nanoparticles and graphene oxide into the deionized water in turn at room temperature, stirring continuously to magnetize the graphene oxide, isolating the black product by filtration, washing with deoxygenated deionized water, and drying in a vacuum drying oven at 50-70degrees Celsius for 4-8 hours to obtain a magnetic graphene oxide nanocomposite; (iv) preparing surfactant modifier is a polyvinyl alcohol solution comprises stirring deionized water at a constant temperature of 60-80degrees Celsius, adding the polyvinyl alcohol dry powder into the deionized water during the stirring process and stirring continuously to obtain a uniform polyvinyl alcohol solution; and (v) stirring the polyvinyl alcohol solution, the ferric oxide nanoparticles and the magnetic graphene oxide nanocomposite, adding sequentially into the polyvinyl alcohol solution, placing the mixed solution in an ultrasonic reactor, dispersing the ferric oxide nanoparticles and the magnetic graphene oxide nanocomposite fully and ultrasonically by the ultrasonic field to obtain the ferric oxide magnetic graphene oxide-polyvinyl alcohol suspension, dropping the ferric oxide-magnetic graphene oxide-polyvinyl alcohol suspension into the syringe, pumping the suspension out of the syringe with a constant-displacement micro-syringe pump, forming a jet toward the fiber collector, turning on the adjustable direct current high-voltage power supply, adjusting the voltage in the range of 15-25kV to carry out the electrospinning process, forming the suspension jet between the injection head of the syringe and the fiber collector to form an electrospun magnetic nanofiber demulsifier, receiving the electrospun magnetic nanofiber demulsifier by the fiber collector, collecting and packaging.