JPH0436736B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a reaction test device that makes it possible to investigate the mode of reaction between a solid and a liquid under high temperature and high pressure. The present invention relates to a reaction test device that can be effectively used in basic experiments for theoretically predicting the reaction rate in reactions in which the reaction rate does not change significantly.

[Prior Art] There are countless reactions between fluids and solids, and they are of great industrial significance. As shown in Figure 2 a to c, the reaction vessels used for this purpose are a reaction vessel (batch) type a in which the solid and liquid contained in the reaction vessel are stirred with a stirrer, and a reaction vessel (batch type) in which the solids and liquid contained in the reaction vessel are stirred with a stirrer. Plug flow is a system that generates a plug flow of liquid.
There are three types: flow) type b, and mixed flow type c, in which the solid and liquid are stirred by a stirrer in the reaction tank while simultaneously supplying the liquid to the reaction tank and discharging the reaction liquid.

In all of the above cases, solid particles are placed in a fluid stream to promote the reaction, but in cases a and c of the same figure, the flow velocity around the particles is not constant, so the reaction rate is Analysis must rely on experience, and many trials are required to find the optimal conditions. In addition, in the case of FIG. 5B, there is a drawback that the rate of reaction progress is different between the inlet and the outlet if left as is.

In contrast to these methods, the rotating disk method described below (Boomer, DRet al. Review
of Scientific Instruments, vol.43, p.225−229,
[1972]) and is widely used.

This rotating disk method involves rotating a solid disk-shaped object and applying a liquid stream to the rotating solid disk, and has the following features.

1. No flow tunnel is required to direct the flow.

2. The amount of solution is small.

3. The problem of uneven flow at the outer edge of the disk is reduced.

4 Since the solution is moving three-dimensionally, Navier
Stokes law can be applied.

5 The thermal mass conductivity coefficient is the same over the entire surface of the disk.

However, this method not only requires a large solid that can be processed into disks;
Since the flow velocity varies depending on the position on the disk, mathematical analysis of the results is not easy. As a result, its application has been limited to a very limited range.

[Problems to be Solved by the Invention] The present invention provides a reaction test that allows elucidation of the solid-liquid reaction mechanism by simple mathematical analysis using a small amount of solid and data from a small number of trials. It provides equipment.

[Means for Solving the Problems] In order to achieve the above object, the reaction test device of the present invention includes an elongated pipe disposed in a pressure chamber in a cylindrical container having heat resistance and pressure resistance, and A propeller is provided at one end of the pipe to generate an axial flow into the pipe for the liquid in the pressure chamber, and a spherical solid to be reacted can be placed at the other end of the pipe, and the pipe is connected to the propeller. Therefore, the length is set to be sufficient to generate plug flow at the solid mounting position in the pipe, and between the pipe and the inner wall of the pressure chamber, in order to cause the liquid that has passed through the pipe to flow back to the base end of the pipe. It is constructed by forming a flow path.

[Operation] To cause a reaction between a solid and a liquid, place a solid sphere at one end of a pipe, inject the required liquid into the pressure chamber to the required pressure, and maintain the liquid at the required temperature. while rotating the propeller. As the propeller rotates, the liquid in the pressure chamber is forced to convect within the pressure chamber through the pipe and the flow path, and becomes a plug flow at the position where the solid ball is installed in the pipe.

In this way, the temperature, pressure, and liquid flow rate are kept constant in the pressure chamber, and a plug flow is generated at the position where the solid sphere is attached, so it is easy to investigate the reaction rate between solid and liquid. This greatly facilitates the mathematical analysis of the reaction mechanism between solids and liquids.

[Example] FIG. 1 shows an example of a reaction test device according to the present invention.

This reaction test device includes a cylindrical container 1 having heat and pressure resistance that can withstand high temperatures (e.g., 400°C) and high pressures (e.g., 400 Kg/cm ² ). One end of the pressure chamber 2 is
An inner lid 3 having a liquid inlet 4 and an outlet 5 is fixed by screwing a cap 6 to close it.
The other end of the pressure chamber 2 is closed by screwing a cap 10 onto an inner lid 7 through which a shaft 9 of a turbine blade type propeller 8 is inserted. This propeller 8 generates an axial flow for the liquid in the pressure chamber 2 by its rotation, but the shaft 9 of the propeller 8 does not protrude from the inner cover 7 to the outside. The driven magnet 11 is configured to be rotatably driven by the action of an external induction magnet 12 which is rotated around the driven magnet 11 outside the inner lid 7. ing.

Further, an elongated pipe 14 made of thin stainless steel and inserted into the pressure chamber 2 is attached to the inner end surface of the inner lid 7. Said pipe 14
In order to make the flow at least at the solid mounting position in the pipe into a plug flow, it is formed to have a sufficient length to generate the plug flow. Specifically, the length of the pipe 14 and the inner diameter (length diameter/inner diameter) of 25 or more. Further, a large number of liquid circulation holes 15 are bored in the pipe 14 at a position close to the part where it is attached to the inner lid 7, and the propeller 8 is positioned inward from the opening position of these circulation holes 15. There is. On the other hand, near the other end of the pipe 14, a net 17 can be removably installed, to which a solid ball 16 that reacts with the liquid in the pressure chamber 2 is attached by bonding or the like. Between,
A flow path 18 is formed for causing the liquid that has passed through the pipe 14 to flow back to the base end side of the pipe 14.

In addition, in the figure, 20 and 21 are fixing nuts, 2
2 and 23 are packings, 24 and 25 are back-up springs, and 26 and 27 are drain holes.

In order to perform a reaction between a solid and a liquid in the reaction test apparatus having the above configuration, the net body 17 to which the solid sphere 16 is attached is attached to the end of the pipe 14, and the liquid is injected from the liquid inlet 4 provided in the inner lid 3. A required liquid is injected into the pressure chamber 2 to a required pressure, the liquid is heated to a required temperature, and the propeller 8 is rotated in this state. As the propeller 8 rotates, the liquid in the pressure chamber 2 enters through the circulation hole 15 provided in the pipe, flows out from the other end of the pipe 14, and returns to the circulation hole 15 side through the flow path 18.
Forced convection is caused within the pressure chamber 2, and a plug flow occurs at the position where the solid ball 16 is installed within the pipe 14.

In this way, the temperature, pressure,
Since the flow velocity of the liquid is kept constant and a plug flow is generated at the position where the solid ball 16 is attached, the solid and
The reaction rate between liquids can be easily investigated, and the mathematical analysis of the reaction mechanism between solids and liquids becomes very easy. In particular, the reaction rate between solids and liquids changes depending on the flow rate, and there are many advantages in industrial chemistry if the optimal conditions for the reaction can be mathematically estimated from data obtained from fewer trials. The above reaction test device examines the influence of flow rate on reaction rate,
It is extremely suitable for elucidating the solid-liquid reaction mechanism through mathematical analysis.

The method of mathematical analysis described above was developed by Levenspiel O.
Chemical Reaction Engineering 2nd ed.”
(John Wiley, NY1972)
It is possible to use the "unreacted core model," which has since been developed by several people.

The above reaction test device can be widely applied to reactions in which the volume of solids does not change significantly during the reaction, such as plating metal surfaces and protecting them with chemicals, examining the safety of underground disposal of radioactive waste, and reducing the risk of damage caused by leaching. It can be widely used as a basic experimental device for theoretically predicting reaction rates during the recovery of metals from high-grade ores.

[Effects of the Invention] According to the solid-liquid reaction test device of the present invention, 1. The amount of solid to be reacted may be small (diameter 3 to 3).
4mm ball).

2. Mathematics is easy because the solid is spherically symmetric. Therefore, it is easy to apply it to reactors actually used in the chemical industry.

3. Unlike the above-mentioned rotating disk method, there is no need to place a large disk inside the container, so the device can be downsized, and as a result, the limits can be greatly expanded to the high temperature and high pressure side. For example, the rotating disk method could only be used up to 100℃ and 1 atm;
The above reaction test device can easily be used up to 400°C and 400 atm.

4. Since the flow rate of the liquid on the solid surface is constant, the relationship with the reaction rate can be accurately measured by changing the flow rate.

You can expect the following effects.

Furthermore, based on these data, we determined the rate-limiting step of the reaction on the solid surface.
We can clarify what exactly it is. Once the rate-limiting mechanism of the reaction is clarified in this way, it is possible to drastically reduce the reaction time, increase the reaction efficiency, etc. by improving only that point.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a reaction test apparatus according to the present invention, and FIGS. 2 a to 2 c are structural diagrams showing an outline of a conventional reaction vessel. 1... Cylindrical container, 2... Pressure chamber, 8... Propeller, 14... Pipe, 16... Solid ball, 18...
...Flow path.

Claims (1)

[Claims] 1. A long and thin pipe is arranged in a pressure chamber in a cylindrical container having heat resistance and pressure resistance, and a propeller is provided at one end of the pipe to generate an axial flow into the pipe for the liquid in the pressure chamber, and A spherical solid to be reacted can be installed at the other end of the pipe, and the pipe is set to a length sufficient to generate a plug flow at the position where the solid is attached in the pipe by a propeller. A reaction test device between a solid and a liquid, characterized in that a flow path is formed between the inner wall of the pressure chamber and the inner wall of the pressure chamber for refluxing the liquid that has passed through the pipe to the base end side of the pipe.