Sulfur Dioxide Absorption With Ionic Liquid In A Rotating Packed Bed

As a kind of non-polluting,thermal stability and renewable green solvent,ionic liquid has attracted the attention of scholars from all fields of life.It can be used in the fields of material preparation,biocatalysts and acid gas absorption.Ionic liquid as an acid gas absorbent,with no pollution,excellent stability,recyclable and other characteristics,is widely popular with today's green chemical society principles.However,due to the high viscosity of the ionic liquid,it has caused the gas-liquid mass transfer efficiency in the conventional reactor to be low,that is,the efficiency of gas absorption is not high,which restricts its further development.RPB is a kind of chemical equipment which enhances the mass transfer of gas and liquid mass transfer.Therefore,this paper applies the super-gravity technology to the absorption experiment of acid liquid to acid gas,prepared different cosolvents of caprolactam tetrabutylammonium bromide[CPL][TBAB]ionic liquid absorption solution.The effect of experimental operating conditions on the desulfurization efficiency of ionic liquid system in high gravity reactor was studied and surely it had the effect of desorption and recirculation.1.Synthesis and characterization of ionic liquids.The[CPL][TBAB]ionic liquid was synthesized by direct synthesis method,and the structure was characterized by nuclear magnetic resonance spectroscopy.It was proved that the high purity[CPL][TBAB]ionic liquid was synthesized experimentally.2.Study on desulfurization of ionic liquid aqueous solution in rotating packed bed.Different concentrations of ionic liquid and water absorption liquid system are prepared,the effects of absorption concentration,high gravity level,gas flow rate,liquid flow rate and absorption temperature on 502 removal rate were investigated,and the effect of desorption recycle absorption was verified.The results show that with the increase of the supergravity factor,the removal efficiency of SO₂ increases,the removal efficiency of SO₂ increases with the increase of the absorption temperature,and the removal efficiency of SO₂ decreases with the increase of gas flow rate.With the increase of liquid flow,the removal efficiency of SO₂ is reduced.The removal efficiency of SO₂ did not increase with the increase of concentration for the different concentration of the absorbing solution.The optimum concentration was 0.5mol/L.In the case of high temperature and low pressure,the desulfurization of the ionic liquid can be recycled and the SO₂ removal efficiency did not decrease significantly after repeated cycles.3.Study on desulfurization of co-solvents with ethylene glycol and polyethylene glycol in rotating packed bed.The effects of the solvent on the desulfurization of the absorbent solution of ethylene glycol and polyethylene glycol were analyzed and compared.Experiments show that the solvent is better for desulfurization of polyethylene glycol system.The influence of the molecular weight of polyethylene glycol on the desulfurization efficiency was determined.Experiments selected the PEG-400 system as the solvent for a follow-up experiment SO₂ absorption solution.The effects of high gravity level,gas-liquid ratio and absorption temperature on the removal rate of SO₂ were investigated.The desorption conditions were investigated and the effect of cyclic desulfurization was verified.Experiments show that the removal efficiency of SO₂ increases with the increase of high gravity level,gas-liquid ratio,SO₂ removal efficiency is reduced.As the absorption temperature increases,the removal efficiency of SO₂ decreases.It is proved that in the case of high temperature and low pressure,the desorption time of the absorption solution with the cosolvent polyethylene glycol is about half of the aqueous solution system.That is,renewable energy consumption is relatively low.It is verified that the desulfurization rate of the absorption solution of the system did not decrease obviously after repeated use.