| The fine coal dewatering is one of the technical problems in the coal processing industry.The use of superabsorbent polymer is a brand-new method to achieve the fine coal dewatering by functional materials.The dehydration effect is good and process is controlled easily,but the recovery and regeneration of resin are difficult.In this paper,the preparation of magnetic absorbent polymer has been presented that the resin can be separated from fine coal by magnetic separation.The magnetic superabsorbent polymer was prepared with chemical transformation has magnetic material Fe3O4 inside.The main factors affecting magnetic susceptibility of the magnetic superabsorbent polymer were studied and the optimum conditions were determined in which the magnetic superabsorbent polymer can be suitably prepared.The structure and properties of magnetic superabsorbent polymer were also tested.Dewatering fine coal with superabsorbent polymer,and studying the impact various factors in the process.The main results are as follows:(1)The results indicated that the content of Fe304 for the magnetic superabsorbent polymer are obviously influenced by such factors as the dipping time and temperature,ratio of Fe3+ and Fe2+ and concentration in the mixture,the concentration of NaOH solution as well as the transformation conditions and so forth.The optimum conditions were,the ratios of ferric and ferrous salts was 2:1,the concentrations of salts was 0.4mol·L-1,impregnate 120min at 70℃ and the solution of was 2mol·L-1.(2)The swelling ratio and equilibrium swelling ratio(ESR)as indicator,capacity of water absorption was investigated.The results showed the water absorption of magnetic polymer was worse than general polymer.The higher the Fe3O4 content,the greater the gap.The swelling kinetic model for polymer was non-Fickon diffusion.In the swelling process,the relaxation rate of macromolecular chains and the diffusion rate of water were fairly.(3)The water retention rate as indicator,capacity and kinetics of water retention was investigated.The results showed under the same conditions,the water retention of the magnetic resin is greater than the normal resin;The water conservation process of superabsorbent polymer is zero order reaction,apparent activation energy Eageneral=3.0166 × 104J·mol-1,Eamagnetic=2.9199 × 104J·mol-1,the constant of reaction rate kgeneral=4.7534×105e-3.0116×104/Rr kmagnetic=3.1710×105e-2.9199×104/RT.This process was an endothermic process,equations of dynamic simulation results conformed very closely to experimental data equation.At the same temperature,the constant of reaction rate kmagnetic<kgeneral indicating that the water retention of resin magnetized was enhanced.(4)Dewatering fine coal use superabsorbent polymer could achieve good results.The moisture content of the fine coal could be reduced below 10%in 30 minutes with 2%resin.The effect of dewatering fine coal use magnetic resin was lower than general resin,indicating a high swelling ratio was a key to dewater fine coal with superabsorbent polymer.Dewatering fine coal with resin reused could still achieve the same effect,but the Fe304 content of magnetic resin declined. |
PDF Full Text Request