Preparation and oil absorption properties of oil-material for corn straw by esterification modification
The oil absorption material for esterified corn straw(ECS)was prepared by esterification modification under microwave assistance with raw corn straw(RCS),alkaline hydrogen,formic acid and acetic acid.The optimal preparation conditions were determined by response surface design with the Box-Behnken method,that was,the mass fraction of formic acid was 7％,the solid-liquid ratio was of 1∶40,the microwave power was of 400W,the reaction temperature was of 100 ℃ and the reaction time was 20min.The oil absorption ratio of ECS for engine oil attained 25.47g/g,which was 1.27％lower than the predicted value of 25.80g/g by regression model and indicated that the model was well simulated.The structures and properties were characterized and tested via infrared spectroscopy,elemental analyzer,the scanning electron microscopy,X-ray diffraction,thermogravimetric analyzer and contact angle measurement instrument.The analysis results showed that there were new peaks in the infrared spectrum of ECS,and the content of O and H elements was reduced,indicating that the esterification reaction had successfully occurred,the surface was rough,its crystallinity was of 42.54％,the temperature of the maximum weight loss rate was increased from 310.1℃ before modification to 352.1℃ after modification,and the hydrophobic angle was increased from 0°before modification to 97.2° after modification.Compared with RCS,the oil absorption rate of ECS was significantly improved.After reuse 9 times,the oil absorption rate of ECS for different oil products could remain more than 70％.This paper can provide a method for the resource utilization of waste corn straw and the treatment of oily wastewater.
raw corn strawmodificationesterificationoil absorption ratio
万方数据
维普
