Dalian University of Technology

Hongtao Yu

Shuo Chen

Xie Quan

Gaoliang Wei

Yanjun Mao

Yaobin Zhang

Wuzhe Quan

Haiguang Zhang

The invention, belonging to the field of membrane technology, presents a method for the direct growth of ultrathin porous graphene separation membranes. Etching agent, organic solvent and polymer are coated on metal foil, and then they are calcined at high temperature in absence of oxygen; after removal of metal substrate and reaction products, single-layered or multi-layered porous graphene membranes are obtained. Alternatively, the dispersion or solution of etching agent is coated on metal foil, on which a polymer film is then overlaid. The obtained sample is subsequently calcined at high temperature in absence of oxygen; after removal of metal substrate and reaction products, single-layered or multi-layered porous graphene membranes are obtained. The method involved in this invention is simple and highly efficient, and allows direct growth of ultrathin porous graphene separation membranes, without needing expensive apparatuses, chemicals and graphene raw material. Additionally, the graphene membranes prepared with this method have controlled pore size, ultrahigh water flux and strong resistance to irreversible fouling.

Method for directly growing ultrathin porous graphene separation membrane

A method for preparation of conductive polymer/carbon nanotube (CNT) composite nanofiltration (NF) membrane and the use thereof. This conductive polymer/CNT composite NF membrane is obtained by polymerizing conductive polymer into a CNT membrane and then in-situ cross-linking with glutaraldehyde under acidic condition. The synthetic method for the conductive polymer/CNT composite NF membrane is simple and has no need of expensive equipment. The prepared membrane has controllable membrane structure and possesses superior electrical conductivity and electrochemical stability. The membrane can couple with electrochemistry for electrically assisted filtration. With the electrical assistance, the membrane can achieve improved ion rejection performance while retaining high permeability by enhancement of membrane surface charge density, which alleviates the permeability-selectivity trade-off. Furthermore, the electrically assisted NF membrane filtration can also enhance the removal for small molecular organic pollutants.

Method of preparation of conductive polymer/carbon nanotube composite nanofiltration membrane and the use thereof

The invention, belonging to the field of biological treatment of pollutants and functional materials, presents a method for the preparation of biofilm carrier with biochar fixed by thermoplastic resin. Extrusion grade polyethylene/polypropylene particles are used as the basic material. One or some combination of plant biochar, straw biochar, rice husk biochar, shell biochar, excess sludge and animal waste biochar are used as the functional material. The biofilm carrier with biochar fixed by thermoplastic resin is prepared by the screw extrusion process, which is a simple, flexible and controllable method, and possesses strong adaptability. The reactor with these biofilm carriers has high removal efficiency of refractory organic pollutants.

Method for the preparation of biofilm carrier with biochar fixed by thermoplastic resin

The invention, belonging to the field of biological treatment of pollutants and functional materials, presents a non-dissolved redox mediator biofilm carrier and its preparation method. The graphene oxide and/or carbonylation modified graphene oxide are used as the non-dissolved redox mediator, which is called as the functional material, and the extrusion grade polyethylene/polypropylene particles are used as the basic material. The non-dissolved redox mediator biofilm carrier is prepared by the screw extrusion process, which is a simple, flexible and controllable method, and possesses strong adaptability. The reactor with these biofilm carriers has high removal efficiency of refractory organic pollutants.

Non-dissolved redox mediator biofilm carrier and its preparation method

The invention, belonging to the field of membrane technology, presents a method for the high-throughput preparation of carbon nanotube hollow fiber membranes. This method contains three major steps. Firstly, the pristine carbon nanotubes (CNTs) are added into a mixture of concentrated nitric acid and sulfuric acid, which is then heated at 40&#x2dc;80&#xb0; C. for 0.5&#x2dc;6 hours. Secondly, the surface-functionalized CNTs and polyvinyl butyral (PVB) are dispersed and dissolved, respectively, in organic solvents at a mass ratio of 1:0.2&#x2dc;1:4&#x2dc;8 to form homogeneous spinning solution, which is squeezed into water as shell liquid with water as core liquid at a flow rate ratios of 0.5&#x2dc;5:1 through a spinneret to form CNT/PVB hollow fibers. Finally, the dry fibers are calcinated at 600&#x2dc;1000 &#xb0; C. for 1&#x2dc;4 hours in absence of oxygen to produce free-standing CNT hollow fiber membranes. The method involved in this invention is simple and highly efficient without needing any templates, expensive apparatuses and chemicals. Additionally, the obtained electrically conductive CNT hollow fiber membranes feature a high porosity, high water flux and strong acid/alkali resistance.

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Liaoning, China

Hongtao Yu