Study On The Stirring And Mixing Characteristics Of CuPc Synthesis Reaction System

Copper phthalocyanine(CuPc)was one of the most important blue organic pigment.In industrial production,copper phthalocyanine was mainly produced by solvent method in batch reactor.To improve the production efficiency,two-step-reaction method was widely used.The reaction in the condensation reactor was complex,which was a solid-liquid-gas three-phase system.To realize homogeneous solid-liquid-gas three-phase dispersion and material fluid circulation in the reactor,the design and operation conditions of the reactor and agitator were required.In addition,the stirring torque of the reactor would change dramatically with the development of the reaction.In this study,the copper phthalocyanine synthesis reaction device was designed and manufactured,and the power curve of the PBT-4 was measured under different experiments.The power curves were compared with the theoretical values calculated by the correlation equation proposed by Shinji Nagata.And the influence of the air flow on the stirring power and RPD in the process of the forms of agitator gas-liquid two-phase mixing system was studied.The reaction process and stirring power consumption in the condensation reactor under different conditions were studied,and the scale-up calculation was carried out based on the experimental data.The rheological properties of copper phthalocyanine-alkyl benzene solvent mixture was studied.The main findings were as follows:At different stages of reaction in the condensation reactor during the reaction process,the drastic change of stirring torque was caused by the change of phase state of materials and apparent viscosity in the reactor.As the apparent viscosity increased,the Reynolds number decreased,and the stirring torque and power also increased.The results show that when the PBT-4 was operated under the baffled condition,the power number of the PBT-4 at the same Reynolds number increased with the increase of the number of layers and liquid level of the reactor.The theoretical power number values were much lower than the experimental values at the low Reynolds numbers.With the increase of stirring Reynolds number,the two were gradually close to each other.Beyond a certain range,the theoretical values began to be higher than the experimental values.This was due to the error caused by the approximate combination of multiple blades into simple twin blades in the Shinji Nagata correlation equation.In the process of stirring the solvent at different stirring speeds with three layers of PBT-4,air was pumped into the bottom of the reactor.When the volume of solvent was 6 L,the stirring power and RPD both decreased with the increase of the air flow.When the solvent volume was 5 L,there was no significant change in stirring power and RPD under different air flow.The operating conditions of the synthesis reaction process were studied.When PBT-4 increased from two layers to three layers,the time of condensation reaction was delayed by 8.86%,and the total reaction time was shortened by 9.11%.The stirring power increased by 2.7%at the beginning of condensation reaction,and the maximum power decreased by 52.7%during condensation reaction.The net energy consumption in the reaction was reduced by 32.5%.When the stirring speed of the agitator was increased from 250 rpm to 300 rpm and 360 rpm,the condensation reaction time was 25.9%and 37.4%ahead,and the total reaction time was shortened by 13.6%and 29.1%,respectively.At the beginning of condensation reaction,the stirring power was increased by 8.2%and 92.4%respectively.In the condensation reaction process,the maximum power was increased by 170.7%and 393.0%respectively.The net energy consumption of the reaction increased by 81.1%and 116.0%respectively.When the solvent content was increased from 2.0 kg to 2.5 kg and 3.0 kg,the condensation reaction time was delayed by 18.6%and 37.3%,respectively,and the total reaction time was extended by 15.0%and 45.7%,respectively.At the beginning of condensation reaction,the stirring power was increased by 51.2%and 59.6%respectively.In the condensation reaction process,the maximum power increases by 26.0%and 62.2%respectively.The reaction net energy consumption increased by 42.0%and 116.0%respectively.The copper phthalocyanine-alkyl benzene solvent mixture system was pseudoplastic,and the consistency coefficient and rheological index increased with the increase of the solid volume concentration of copper phthalocyanine.The surface morphology of copper phthalocyanine crystals,which were the rod-like structure of crystal particles and clusters were observed by SEM.In the Scale-up calculation under Rf=2061.6,the stirring power data calculated based on the principle of maintaining the same PV was the most reasonable:for a reactor of 20.62 m3,average stirring power Pa*=55798 W before condensation reaction,and maximum stirring power Pm*=109265 W after condensation reaction.