Study On Kinetics Of Synthesis Of Calcium Formate By Calcium Hydroxide Carbonylation

The calcium formate, is widely applied not only as a new developed feed additive, which is fit for all kinds of animal feed as acidifier acidulant, preservative and antimicrobial, but also as desulfurizer of fuel, food additive, drilling auxiliary in petroleum industry, regulator of plant growing, setting accelerator in the cement industry, tanning auxiliary and so on. More and more attraction has been taken on the synthesis of calcium formate since when it was approved to be legal feed additive as feed additive by Departmen of Agriculture.In this experiment, the effects of reaction temperature, reaction pressure, solid content of calcium formate, stirring speed on the reaction rate of calcium hydroxide carbonylation were investigated. The results showed that with the increase of temperature and pressure, the carbonylation reaction rate turned faster. As long as the partial pressure of carbon monoxide remained unchanged, filled nitrogen had little influence on the reaction. The reaction rate increased with the increase of stirring speed, and reaction rate woule almost remain stable when the stirring speed reaches a certain value.Researches of calcium hydroxide carbonylation were systematically carried out at different operating conditions, including reation temperature, pressure, etc. The experimental results showed that the reaction of calcium hydroxide carbonylation for calcium formate synthesis was almost no other vice reactions. And the reaction temperature and pressure had almost no effect on the selectivity of calcium format.The qualitative analysis of the product by means of XRD that small amount of calcium carbonate was formed during the calcium formate formation, thermodynamic analysis indicates that the equilibrium constant the carbon monoxide hydration reaction is smaller, but the presence of calcium hydroxide which can remove formic acid from carbon monoxide hydration out of the reaction system can promote the reaction continue till the reaction end.In the semi-batch steady-state operating mode, the elimination of mass transfer resistance (including gas-liquid interface, liquid-solid interface and solid interior) was validated, and the effects of different operation conditions range were found. In the following operating conditions:temperature433-473K, pressure2.5-4.4MPa, solid content of calcium formate0.0913g/L, stirring rate1100RPM, the kinetic experiments were carried out and experiment data were collected. So the reaction kinetic equations were built:...