JPH0365489B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic titration analyzer for automatically measuring the concentration of a liquid.

[Conventional technology]

In general, in the operation management of chemical reaction equipment, treatment equipment that adds chemicals as treatment agents, and water quality management of industrial water and industrial wastewater, etc.
Chemical analysis is indispensable, and in particular, for quality control and process control in the production process of chemical factories, it is extremely important to always obtain highly accurate measurement values and feed back this to the production process. Chemical analysis has been carried out with the improvement of technical proficiency and analytical equipment.

[Problem to be solved by the invention]

However, not only is there a limit to the level of skill of the analyst, measurements take too much time, individual errors on the part of the analyst are unavoidable, and when so-called repeated continuous analysis is performed, the analyst is overburdened. There were problems such as the amount of labor involved.

The present invention aims to solve these conventional problems, and aims to provide an automatic titration analyzer that can easily produce highly accurate measurement values at all times without requiring high levels of skill on the part of the analyst. This is the purpose.

[Means to solve the problem]

The present invention consists of a sampling mechanism that collects a predetermined amount of a sample for analysis using a sampling burlet and supplies the sample to an analysis cell, and an oxidation ring source potential measuring electrode that converts changes in the physical properties of the sample into electrical quantities and outputs them to the analysis cell. and an analysis mechanism equipped with a PH measuring electrode and a stirring/discharging member for stirring and discharging the sample and reagent, and a titration mechanism for titrating predetermined amounts of an oxidation ring reagent and an alkaline reagent into the analysis cell using a titration bottle, respectively. An automatic titration analyzer characterized in that it is equipped with a control mechanism that instructs to start and stop the sampling mechanism, the analysis mechanism, and the titration mechanism so that each mechanism operates separately for a predetermined time and in a predetermined order. It is.

[Effect]

The analyzer of the present invention is applied to the concentration control of an etching solution for dissolving and removing a specific amount of copper from an electric circuit board such as a printed circuit board, and is used to control the concentration of an etching solution containing hydrogen peroxide, sulfuric acid, and copper. The concentration can be automatically maintained within a predetermined range, greatly streamlining the etching process.

In other words, this device automatically titrates and analyzes the concentration of the etching solution using sequence control, and feeds back the analysis results to the etching solution concentration adjustment mechanism to easily and accurately manage the concentration of the etching solution. There is.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings.
This is an example in which the concentration of an etching solution, which is a sample for analysis, is simply applied. It consists of a sample sampling mechanism S, a reagent titration mechanism T, an analysis mechanism A, and a control mechanism C. Consisting of a hydrogen metering injection pump P ₁ , a sulfuric acid metering injection pump P ₂ and an etching liquid circulation pump P ₃ , the discharge sides of the injection pumps P ₁ and P ₂ are connected to an etching device (not shown), and the circulation pump P ₃ The discharge side of is connected to an etching device via a copper sulfate crystallization and recovery device (not shown) by a pipe line.

The sampling mechanism S includes, as main elements, a circulation pump 1 for a sample to be analyzed, an overflow box (overflow cell) 2, and a sampling module 3 which is a piston pump type metering pump (equipped with a check valve). It is connected to the analysis cell 9 through piping with solenoid valves SV ₄ and SV ₅ . The circulation pump 1, the overflow box 2, and the sample storage tank 4 constitute a sample circulation system, and the sample (etching solution) enters the overflow box 2 by the circulation pump 1 and is constantly refreshed.

The titration mechanism T also includes an alkaline reagent tank 5, a potassium permanganate reagent tank 6, and titration bottles 7 and 8 having the same structure as the acid bottle 3 for titrating these reagents to the sample in the analysis cell 9. We are prepared.

Next, the analysis mechanism A includes a container that receives the sample and reagent, that is, an analysis cell 9, and a solenoid valve SV that supplies a cleaning liquid for cleaning the inner wall of the container or a dilution liquid for diluting the sample in the analysis cell 9. ₁ , a liquid level controller (level switch) 10 for controlling the supply amount of cleaning liquid and diluting liquid to a predetermined amount, a PH measuring electrode 11, an oxidation-reduction potential measuring electrode 12, and an analysis cell. An air pump 13 (a soda lime pipe for removing carbon dioxide gas is connected to the discharge side) for stirring the content liquid in 9 and a discharge pump 14 for the content liquid are connected to electromagnetic valves SV ₂ and SV ₃ . It is provided with piping.

On the other hand, as the control mechanism C, a control section 15 equipped with a microcomputer, a display, and a converter is used, and includes solenoid valves SV ₁ to _{SV 5} , a sampling chamber 3, a titration chamber 7, 8,
Operating the air pump 13 and discharge pump 14 in a predetermined order for a predetermined time; Opening and closing the solenoid valve SV ₁ in response to a signal from the level switch 10; PH measuring electrode 11; redox potential measuring electrode 1.
2, when a predetermined pH or potential is reached, the operation of the titration bottles 7, 8 is stopped, the end point of the titration is detected, and the titration amount of the reagent at the end point is determined by the titration bottles 7, 8. The hydrogen peroxide concentration or sulfuric acid concentration of the sample is calculated from this reading amount, and when the obtained concentration is lower than a preset concentration, the difference between the set concentration and the measured concentration is converted into time. , operating the injection pump P ₁ or P ₂ for that time; and operating the circulation pump P ₃ when the copper concentration of the sample obtained in the same manner is higher than a preset concentration to remove the excess copper. Transfer to a crystallization recovery device to separate and recover copper sulfate, and return the separated liquid to the etching device; display and record the measured concentrations of hydrogen peroxide, sulfuric acid, and copper; and when these become abnormal values. It is configured to perform functions such as issuing an alarm.

This automatic titration analysis control device performs a series of analysis operations and etching solution concentration adjustment operations in accordance with the output from the control mechanism C in the following order.

Analysis operation (1) Preparation of sample (i) Co-washing of analysis cell 9 with sample Open solenoid valves SV ₄ and SV _5, operate sampling chamber 3, and inject a certain amount of sample into analysis cell 9. Open the solenoid valve SV ₃ and operate the air pump 13 to agitate the sample for a certain period of time.

Next, open solenoid valve SV ₂ and discharge pump 1.
4 for a certain period of time to discharge the sample. Repeat the above operation for the set number of times.

(ii) Washing the analysis cell 9 After opening the solenoid valve SV ₁ and injecting tap water to the cleaning level L ₁ , open the solenoid valve SV ₃ and operate the air pump 13 to stir the tap water for a certain period of time.

Next, tap water is discharged in the same volume as in (i) above. This operation is repeated a set number of times.

(iii) Injecting dilution water and sample into analysis cell 9 In the same manner as in (ii), tap water was diluted to level L _2.
After injecting up to 100 ml, inject a certain amount of sample in the same manner as in (i). Next, the air pump 13 performs dilution and stirring and mixing of the sample for a certain period of time.

(2) Titration analysis (i) Titration of sulfuric acid concentration NaOH or Na ₂ CO ₃ is used as the reagent.

(ii) Titration of total copper concentration Same as in (i) above, but acidity and total copper analysis can be performed by titration on the first floor if the sampling points are the same as in this example. After titration of acidity or total copper is completed, discharge pump 1
4 is operated for a certain period of time to discharge the liquid inside the analysis cell 9.

(iii) Titration of hydrogen peroxide concentration Prepare analysis cell 9 with the same volume as in (1)-(i) above.
After performing co-washing, the sample dilution liquids are accommodated in the analysis cell 9 according to the volumes (1)-(ii) and (iii). Titration is then carried out using KMnO ₄ as reagent. Discharge pump 1 after titration
4 is operated for a certain period of time to discharge the liquid inside the analysis cell 9.

Etching solution concentration adjustment operation, sample concentration display, etc. (1) Read the titration amount of the analytical reagent at the end point of titration and calculate the sample concentration such as sulfuric acid concentration.

(2) When the obtained hydrogen peroxide concentration or sulfuric acid concentration is lower than the preset concentration, convert the difference between the set concentration and the measured concentration into time, and operate the injection pump P ₁ or P ₂ for that time. In addition to replenishing sulfuric acid or hydrogen peroxide when activated, it also displays the measured concentration as described above.

Here, to provide a supplementary explanation of the relationship between the PH measuring electrode 11, the redox potential measuring electrode 12, the control mechanism C, and the titration modules 7 and 8, changes in the physical properties of the sample due to the titration operation are momentarily output to the control mechanism C by each of the electrodes. However, the control mechanism C detects the rate of change in the physical properties with respect to the reagent titration amount, detects the end point of the titration based on this, performs a memorization operation for the end point, and also performs an operation corresponding to the magnitude or small change in the physical properties. The reagent titration rate is adjusted to be low or high, respectively, and the operation of the titration chambers 7 and 8 is stopped when a preset pH or oxidation ring potential is reached.

The above-described operations are repeated, and the circulation pump _P3 continues to operate until the subsequent titration analysis outputs that the copper concentration is below the set concentration. In this way, circulation pump P ₃ measures concentration>
At the set concentration, it becomes ON (activated), and when the measured concentration ≦
It performs ON-OFF operation such that it turns OFF at the set concentration.

Although the automatic titration analyzer of the above embodiment was equipped with an etching solution concentration adjustment mechanism, this may be omitted.

As a modification of the above embodiment, the overflow box from the sample storage tank 4 is made to flow into the overflow box 2, the air pump 13 is replaced by a stirrer with stirring blades, the analysis cell 9 is The discharge pump 14 is omitted, and the discharge side of the discharge pump 14 is connected to the analysis cell 9.
A cleaning liquid supply pipe is connected to the sampling chamber 3 and the titration chamber 7, 8 to clean the parts in contact with the liquid. It is also possible to arrange a plurality of sampling mechanisms S, titration mechanisms T, and analysis mechanisms A in parallel, so that analysis operations are always performed in one of the analysis cells 9. In this case, it is recommended to use a gear pump instead of the sampling chamber 3.

Note that a soda lime pipe for removing carbon dioxide gas is connected to the discharge side of the air pump 13;
This is to make air a gas that is chemically inert to the liquid contained in the analysis cell 9, and inert gas such as _N2 gas can be used instead of air from which carbon dioxide has been removed. Depending on the type of the content liquid, air may be directly supplied for stirring.

The device of the present invention can be applied to any titration analysis method as long as the physical properties or chemical properties of the sample change by titration of a reagent. It can be used extremely effectively for controlling the supply amount of any drug, raw material, or auxiliary material, controlling the quality of intermediate or final products in various industrial fields, and streamlining analytical operations in water quality control of industrial water and industrial wastewater. I can do it.

〔Effect of the invention〕

The present invention consists of a sampling mechanism that collects a predetermined amount of a sample for analysis using a sampling chamber and supplies the sample to an analysis cell; Equipped with an analysis mechanism equipped with a PH measuring electrode and a stirring/discharging member for stirring and discharging the sample and reagent, and a titration mechanism that titrates predetermined amounts of a redox reagent and an alkaline reagent into the analysis cell using titration bottles. By providing a control mechanism that instructs the sampling mechanism, analysis mechanism, and titration mechanism to start and stop each mechanism individually for a prescribed time and in a prescribed order, highly accurate measurement values can be obtained almost unattended. It is now possible to obtain samples quickly and repeatedly in a continuous manner, enabling feedback control and significantly streamlining process and quality control of the sample source (e.g. etching process), resulting in significant labor savings.
This has the effect of simplifying the maintenance and management of the sample source device and improving and stabilizing product quality.

[Brief explanation of drawings]

The drawing is a flow sheet of an embodiment of the present invention. 1...Circulation pump, 2...Overflow box, 3...Sampling barrel, 4...Sample storage tank, 5...
Alkaline reagent tank, 6...Potassium permanganate reagent tank, 7, 8...Titration bottle, 9...Analysis cell, 10...Level switch, 11...PH measurement electrode, 12...Redox potential measurement electrode, 13...
... Air pump, 14 ... Discharge pump, 15 ... Control section, 16 ... Supply pipe, L ₁ ... Cleaning level, L ₂
…Dilution level, P ₁ , P ₂ … Infusion pump, P ₃ …
...Circulation pump, SV ₁ to _{SV 5} ... Solenoid valve.

Claims (1)

[Scope of Claims] 1. A sampling mechanism that collects a predetermined amount of a sample for analysis using a sampling chamber and supplies the sample to an analysis cell, and an oxidation ring element that converts changes in the physical properties of the sample into electrical quantities and outputs them to the analysis cell. An analysis mechanism equipped with a potential measuring electrode, a pH measuring electrode, and a stirring/discharging member for stirring and discharging a sample and a reagent, and a titration bottle for titrating predetermined amounts of an oxidation ring source reagent and an alkaline reagent into the analysis cell, respectively. an automatic titration mechanism, and a control mechanism for instructing start and stop operations to operate each of the sampling mechanism, analysis mechanism, and titration mechanism separately for a predetermined time and in a predetermined order. Titration analyzer. 2. The sampling mechanism has a sample circulation system in which a sample storage tank for the sample and an overflow box are connected via a pipe line including a circulation pump, and sucks a predetermined amount of the sample into the overflow box and discharges the sample. 2. The apparatus according to claim 1, further comprising a sampling chamber. 3. The apparatus according to claim 1, wherein the analysis mechanism is provided with a cleaning liquid supply means for cleaning the liquid contact part of the analysis cell. 4. The apparatus of claim 1, wherein the sampling chamber and the titration chamber are piston pumps equipped with check valves.