Melt Electrospun Ultrafine Fibers And Marine Oil Spill Recovery Application Research

Marine oil spill causes tremendous problems.Normal oil sorbents in response to marine oil spill can be categorized into organic natural sorbent, inorganic mineral sorbent and synthetic sorbent. Polypropylene fibers fabricated by melt blow method have been mass-produced and widely used. However, because of the coarse fiber diameter, uneven fiber distribution, poor mechanical performance and low oil sorption capacity, melt blown fibers became less capable in dealing with huge marine oil spill. By the use of self-made melt differential electrospinning device and the tunning of processing parameters, micro-nano hierarchical polypropylene ultrafine fibers and biodegradable ultrafine fibers were made. Characterization such as SEM, contact angle and oil recovery performance were conducted.For polypropylene fibers, within a certain range, with the increase of spinning voltage, fiber diameter became smaller. The smallest fiber is 1.11μm under the voltage of 65 KV. Within a certain range, with the increase of spinning temperature, fiber diameter became smaller. The smallest fiber is 0.71 μm under the temperature of 230℃. After hot-pressing, the porosity of fibrous material dropped from 90%-99% to 60%-70%. Micro-nano hierarchical polypropylene ultrafine fibers were made through SiO2 blending and HCL etching. It is found that there is no evident relation between voltage, temperature and water contact angle of fiber. The contact angle of two micro-nano hierarchical ultrafine fibers were 156° and 152°, which is superhydrophobic. The oil contact angel of polypropylene is 0°, which is super oleophilic. Oil recovery test showed that oil sorption capacity increased with the decrease of fiber diameter and oil sorption capacity increased with the decrease of fiber porosity. After the reuse of 7 times,68% oil sorption capacity is still maintained. Oil sorption dynamics demonstrated that oil sorption process followed the Lagergren second order model. Oil sorption thermodynamics demonstrated that physical sorption is the main force assisted with weak chemical sorption. Sorption process is spontaneous and oil sorption capacity decreased with the increase of temperature. The change of entropy decreased during the whole sorption process.For polylactic acid, the impact of polyethylene glycol, hyperbranched polymer and sugar esters on fiber structure is investigated. Orthogonal experiment demonstrated that smallest fiber of 870 nm is obtained with air temperature of 100℃, air velocity of 90 m/s, voltage of 70 kV and PEG concentration of 8%. Smallest fiber of 896 nm is obtained with the addition of 8% hyperbranched polymer H203. Smallest fiber of 1.36 μm is obtained with the addition of 8% sugar esters. Water contact angle increased with the decrease of fiber diameter. Oil recovery test showed that the relation between PLA fiber structure and oil sorption capacity followed the same trend. After the reuse of 6 times,36% oil sorption capacity is still maintained.Kapok/polypropylene fiber with a ratio of 2:10 possess an oil sorption capacity of 157%. Tire/polypropylene fiber with a ratio of 3:10 possess an oil sorption capacity of 156%. After reuse of 7 times, two kinds of fiber can possess an oil sorption capacity of around 126%.