Preparation And Adsorption Behavior Of Cellulose - Based Oil Absorbing Materials

Butyl methacrylate graft-modified noil fiber (BMA-g-Noil) with excellent oil absorptive performance was synthesized by free radical polymerization with cotton noil (Noil) as substrate, butyl methacrylate (BMA) as grafting monomer, potassium persulphate (K2S2O8) as initiator and divinyl benzene (DVB) as crosslinking agent. The morphologies, chemical structures, crystallinity and thermostability was investigated using TEM、FTIR、XRD and DSC-TG. Furthermore, several parameters were considered to evaluate the sorption capacity of the modified cellulose fiber, such as ratio of the Butyl Methacrylate, potassium persulphate and the divinyl benzene, reaction time and polymerization temperature. Then oil types, oil slick concentration, pH and temperature were considered as the variable to evaluate factors affecting oil removal efficiency of the graft-modified noil fiber. The adsorption kinetics, isotherm and thermodynamics of the diesel on BMA-g-Noil were studied on the condition of oil-water mixed system to demonstrate its adsorption mechanism. The results showed that under the optimum synthesis conditions:m(Noil):m(BMA):m(K2S2O8):m(DVB): =1:1.5:0.025:0.63,75℃,4h, the modified cellulose fiber would obtain better qualities of lipophilicity and hydrophobicity. The oil-absorption rate of the BMA-g-Noil increases with an increase in viscosity. When the BMA-g-Noil was used for oil recovering, the optimum experimental conditions of adsorption were as following:oil-water mixed system is neutral, temperature is 35 ℃, oil slick concentration is more than 50g/L, and its best oil absorption ratio is 14.9g/g and its water absorption ratio is 1.2g/g. At the same time, the BMA-g-Noil has shown a better characteristics of buoyancy, this means that it would be easier to be utilized to deal with oil cleanup. Its adsorption process can be described through the pseudo-second-order kinetic model at 20 ℃, and its adsorption isotherm is closely fitted with the Temkin isotherm model, which suggests that the adsorption of diesel on BMA-g-Noil can be regarded as chemical adsorption. Through the thermodynamics analysis on temperature in the range of 20-35℃, the adsorption enthalpy change △H>0 and the adsorption free energy change △G<0 were observed, which indicated that the adsorption process of the diesel on BMA-g-Noil is endothermic and spontaneous.Graphene modified noil fiber (RGO/Noil) with excellent properties in oil-absorption and oil-retention was produced by heating and stirring with high-temperature reduction, the cotton noil and graphene oxide (GO) was chosen as substrate and modifier. The morphologies, chemical structures, crystallinity and thermostability of the RGO/Noil was investigated using TEM、FTIR、XRD and TG. And we chose the graphene oxide concentration, stirring temperature and reduction temperature as the variable to determine the optimum preparation process. Furthermore, we investigate the effect of oil types and oil slick concentration on absorbency of RGO/Noil and analysis its oil-retention and reusability. The results showed that optimum process conditions were:the graphene oxide concentration is lmg/mL, stirring temperature is 90 ℃, and the reduction temperature is 150 ℃. The oil absorbency of RGO/Noil to machine oil, soybean oil, diesel and liquid paraffin is 25.7, 26.2,24.2 and 22.8g/g. It’s contact angles against distilled water is 122.46°, which indicate that the RGO/Noil has excellent water repellency and lipophilicity.