A novel preparation method for polyimide nanofiltration membranes, developed by the Daqing Chemical Research Center, has recently been granted a national invention patent. This innovative technology enables the production of polyimide nanofiltration membranes that are highly effective in recovering lube ketone benzene dewaxing solvents.
For many years, solvent dewaxing has remained a critical process in the production of lubricant base oils. Traditionally, the dewaxed solvent is separated from the oil-solvent mixture through distillation and then recycled. However, this repeated circulation of solvents leads to significant energy consumption, which has become a major obstacle in expanding lubricant and paraffin production. To address this challenge, researchers at the Daqing Chemical Research Center have introduced an efficient and energy-saving alternative using membrane separation technology.
The process begins with the synthesis of a soluble polyimide, which is then formulated into a casting solution. A thin film is created using a phase inversion method, followed by solvent exchange and heat treatment to obtain the final nanofiltration membrane. The resulting polyimide membrane exhibits a high rejection rate for lubricating oil under specific operating conditions, while allowing for a high permeate flux of the solvent.
Experimental results demonstrated that the polyimide nanofiltration membrane achieved a rejection rate exceeding 90% across a temperature range from -18°C to room temperature, under a pressure of 3 MPa. Additionally, the flux of ketobenzene-based mixed solvents exceeded 12 L/m²·h, meeting all industrial application requirements. This breakthrough not only enhances the efficiency of solvent recovery but also significantly reduces energy consumption, offering a sustainable solution for the lubricant industry.
Di-Tert-Butyl Peroxide,Tert-Butyl Peroxide,Bis(Tert-Butyl) Peroxide,Dtbp Di-Tert-Butyl Peroxide
Jiangsu Zhongluman New Material Technology Co., Ltd , https://www.rozhmch.com