CN1029531C - Automatic titrimeter for measuring resistance of titration liquid - Google Patents
Automatic titrimeter for measuring resistance of titration liquid Download PDFInfo
- Publication number
- CN1029531C CN1029531C CN 92113514 CN92113514A CN1029531C CN 1029531 C CN1029531 C CN 1029531C CN 92113514 CN92113514 CN 92113514 CN 92113514 A CN92113514 A CN 92113514A CN 1029531 C CN1029531 C CN 1029531C
- Authority
- CN
- China
- Prior art keywords
- constant
- measuring
- measurement
- cup
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
The present invention adopts a new measurement principle that the volume measurement of titration liquid is directly converted into an electric quantity measurement. A measurement cup of 30 ml or 50 ml is manufactured by using polytetrafluoroethylene, and two parallel electrodes made from precious metal materials are filled in the measurement cup; the body resistance R corresponding to titration liquid with a certain volume V is measured, and V is in inverse proportion to R, namely V*R=C(a constant); the pulse power source of constant flow of R is measured, and the system is placed in a constant-temperature container of 34.95 DEG C to 35.05 DEG C. Other parts of the device are used as a high-precision potentiometer for measuring equivalent points and a combined pH glass electrode of the potentiometer, and an electromagnetic valve of the effluent titration liquid is controlled; the titrating liquid flows out of the electromagnetic valve through a fast path and a slow path. A temperature measurement probe head is arranged in a sample, the device is controlled by a monolithic computer, and after measured data is automatically corrected through temperature, the concentration and the pH value of the sample are displayed through digitals.
Description
The present invention relates to the autotitrator of a kind of analytical chemistry automatic measurer-measurement vs bulk resistor design.
Titration technique is that general chemical analysis chamber, inspection department generally use classical measuring method, and at present majority is still used manually-operated, and for the not only time-consuming expense manpower of batch samples titration but also easily make mistakes, autotitrator provides great convenience for the work in this field.Have the autotitrator of multiple model at present both at home and abroad, the automatical potentiometric titrimeter series of Shanghai thunder magnetic instrument plant for example, U.S. COLE-PARMER instrument company autotitrator, the Ao Lilong research ORiON9600 of company limited autotitrator, the TTP2 of Comef S.A autotitrator, Switzerland plum Teller (METTLER) company product etc.The gordian technique of autotitrator is accurately measuring fast of vs volume, the principle that adopts has following several: the plunger-type structure that (1) drives with stepper motor, (2) electric pulse control quantitative gas extrudes vs, and the measurement of (3) control vs constant flow rate oozes the time.Relevant patent of invention has (a) to measure the electric capacity (notification number 2000149) of solution and additional electrodes generation, (b) the vs method (notification number 1042989) that weighs with scale, above-mentioned several patent documentation is reported in this respect, most complex structure manufacturing process have certain degree of difficulty, instrument cost height, what have then may be difficult to popularize use because of the mensuration precision is low.
The objective of the invention is to overcome the deficiency of prior art, provide a kind of simple in structure, the automaticity height, easy to operate, the measuring accuracy height.The instrument cost is low, the instrument that can generally promote the use of and produce in enormous quantities.
The realization technical solution of the present invention is:
With the bulk resistor of solution measure of precision method as liquor capacity or liquid level.(for example resistivity is 10 to suppose certain electric conductivity is arranged the solution that will measure
2Ω mm
2/ m is following) be contained in the column type container that is shaped as rule, can think that the height of the volume of solution and column shape container is in direct ratio, put two parallel poles in the short transverse of container, with the constant-current pulse power supply from the corresponding resistance R of electrode measurement liquor capacity V, V and the R relation of being inversely proportional to, be the VR=C(constant), if known a certain standard volume V
0(can by additive method such as the accurate weighing of balance) records corresponding resistance value R
0, obtain constant C, for a kind of solution, different volumes V can draw by measuring corresponding resistance R value.
By novel autotitrator of above method design, its primary structure is all seen principle schematic, this device system is made up of reservoir (3), solenoid valve (5,10,11), measuring cup (8), potential electrode (7), sample cup (13), d.c. motor parts such as (16), and is existing that each Component Design principle and using method division is as follows:
Titrator measuring cup (8) can be got different shapes, to get right cylinder best from easy to process, consider that from performance the slender cylinder electrode distance is near, make and be stranded energy, the little error of resistance value is big, flat making of measuring cup electrode and resistance measurement are all favourable, can increase measuring error but the microvibration of instrument produces the fluctuation of liquid level, and measuring cup can be by stable chemical performance, the material of adsorption moisture is not made, as glass or teflon.
In the cup two horizontal survey electrodes (7) and level control (LC) electrode (6) are set, electrode (7) shape is a cylinder, diameter 0.5～2mm, diameter is difficult to for a short time guarantee that all even device of processing is parallel, and the current density Da Yi on surface contamination makes measurement unstable, surface area is little, measured resistance value can reduce measuring error greatly, choose the big potential electrode of body diameter, the little error of resistance value can increase, but to processing, assembling and prevent to stain and all be beneficial to, the material of electrode is good by electric conductivity, the precious metal material of chemical stabilization is made, for example platinum (Pt), gold (Au), other metals of iridium (Ir) or plating gold.
The power supply of measuring resistance is without direct current, because direct current is to the solution effect of producing electrolysis, the also very easy contamination of electrode surface, adopt the constant-current pulse power supply of frequency 500～5000Hz, pulse current 50～500 μ A, too the corresponding lower measuring voltage of Ruo electric current strengthens measuring error, but too big electric current can influence the life-span of electrode, causes and measures instability.
Measurement is by Single-chip Controlling, and long-time energising is unfavorable to the life-span of electrode, generally only gets the mean value of measuring for 5～10 seconds.Because the relation of the resistance value of solution and temperature is very big, temperature increases by 1 ℃ of resistance value and reduces by 2% approximately.In order to guarantee measuring accuracy 0.1～0.2%, reservoir (3), solenoid valve (5,10,11), measuring cup (8) are placed in the constant temperature system (9), temperature constant is than slightly high 35～40 ℃ of room temperature, constant temperature precision ± 0.01～0.05 ℃.
The remainder of instrument, vs is through electromagnetic valve V2(10) piece passage and V3(11) slow channel inflow sample cup (13).In the practical application, the concentration range of the most known samples of batch samples.For example estimate to add 10ml titrant, emit 9ml fast by Single-chip Controlling earlier, close fast passage then, only flow into sample cup, so both saved titration time, guarantee measuring accuracy again by the slow channel.If can't be scheduled to the quantity of titrant in advance, titrant is flowed into sample cup just only start from scratch by the slow channel.The magnetic stirrer (15) that has direct current generator (16) to drive in the sample liquid evenly mixes sample liquid fast, and the pH value of sample liquid is measured by combined type pH glass electrode (12), provides signal at stop slug flow channel valve when equivalent point.The pH value of solution is relevant with temperature.Temperature measurement probe (14) is housed in sample cup, and sample concentration and pH value that numeral shows all are through the automatic revised result of temperature.
Vs is from filling opening (1) reservoir (3) of packing into, 1 liter of volume.In the bottle platinum filament temp-controlling element (2) is housed, after the start, heating automatically, Controllable Temperature is built in 35 ± 0.05 ℃.When system reached and keep this temperature, valve V1 opened, and vs flows into measuring instrument, when liquid level touch controls electrode (6), and valve-off V1.Tapping valve among the figure (4) is provided with for changing vs.
This instrument has related parameter by 8031 Single-chip Controlling with the keyswitch input, the concentration of digital show sample and pH value, and the user can also import computing formula, and instrument provides the result of requirement automatically.
The autotitrator that the present invention measures the design of vs bulk resistor has following characteristics:
1, the present invention casts aside the design concept of existing domestic and international autotitrator, with measuring the measure of precision of solution body resistance as liquor capacity.
2, autotitrator of the present invention is simpler than existing Instrument Manufacturing Technique, structure, measuring accuracy height, easy to operate.Be convenient to use with computer interconnection.
3, the present invention is applicable to the measurement of analytical chemistry field titration volume or the volume of other conducting solutions, level gauging.
4, autotitrator of the present invention, cost is well below existing same quasi-instrument, can be mass-produced to popularize and use, 11800 yuan of existing every prices of thunder magnetic instrument plant product, 10,000～20,000 dollar of external every price of instrument, the cost of instrument of the present invention is estimated 3000～4000 yuan, prepares 7000 yuan of prices.
Description of drawings:
Figure: the autotitrator synoptic diagram of measuring the design of vs bulk resistor
Among the figure: the 1-filling opening,
The 2-Pt temp-controlling element,
The 3-reservoir,
The 4-tapping valve,
5-solenoid valve V1,
The 6-control electrode,
The 7-potential electrode,
The 8-measuring cup,
The 9-constant temperature system,
10-solenoid valve V2,
11-solenoid valve V3,
The compound pH electrode member of 12-,
The 13-sample cup,
The 14-temperature measurement probe,
The 15-magnet rotor,
The 16-d.c. motor.
Embodiment: a kind of embodiment by the autotitrator of measuring the design of vs bulk resistor:
(1) measuring cup of titrator, use stable chemical performance, the glass or the teflon that do not absorb moisture content are made, teflon is easily processed, and is difficult for breaking, and chemical property is highly stable, the surface is the water pearl not, be more suitable in doing measuring cup, the size of cup has two kinds of 30ml and 50ml, body diameter with highly equate.
(2) potential electrode stable chemical performance, the good iridium that conducts electricity is made, also available brass gold-plated electrode, the diameter phi 1mm of electrode, long 30mm, two electrodes apart from 30mm, the depth of parallelism of electrode requires error ± 0.03mm.
(3) measuring resistance constant-current pulse power supply, electric current 100 μ A, pulsed frequency 1KHz measures by 8301 Single-chip Controlling, gets the mean value of measuring for 10 times after 10 seconds of switching on.
(4) vs constant temperature is at 35 ± 0.05 ℃.
Claims (5)
1, a kind of autotitrator, adopt the measure of precision of the bulk resistor (or electricity is led) of isopulse current measurement solution as liquor capacity or liquid level, this titrator comprises reservoir (3), solenoid valve (5,10,11), measuring cup (8), potential electrode (7), sample cup (13), d.c. motor (16), it is characterized in that measuring cup (8) is provided with two parallel poles (7) and level control (LC) electrode (6) along short transverse, vs enters measuring cup (8) by reservoir (3) by solenoid valve (5), adopt the corresponding resistance R of constant-current pulse power measurement liquor capacity V, utilize VR=C (constant) to obtain vs volume V, described reservoir (3), solenoid valve (5,10,11) and measuring cup (8) all place in the constant temperature system (9).
2, titrator according to claim 1 is characterized in that described measuring cup (8) volume is 30～50ml, can select for use glass, rigid plastic to make, but is best with the polytetrafluoroethylmaterial material, the physical dimension of cup design diameter and height approximately equal.
3, titrator according to claim 1, it is characterized in that described potential electrode (7) diameter phi 1mm, length 30～50mm is with other metals of precious metal material such as platinum (Pt), iridium (Ir) or plating gold, two parallel poles distance, 30 ± 0.03mm.
4, titrator according to claim 1 is characterized in that measuring solution body resistance, uses the constant-current pulse power supply, frequency 500～5000Hz, electric current 50～500 μ A.
5, titrator according to claim 1 is characterized in that measuring liquid and places constant temperature system, 35～40 ℃ of temperature, constant temperature precision ± 0.01～0.05 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 92113514 CN1029531C (en) | 1992-12-02 | 1992-12-02 | Automatic titrimeter for measuring resistance of titration liquid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 92113514 CN1029531C (en) | 1992-12-02 | 1992-12-02 | Automatic titrimeter for measuring resistance of titration liquid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1075210A CN1075210A (en) | 1993-08-11 |
| CN1029531C true CN1029531C (en) | 1995-08-16 |
Family
ID=4946441
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 92113514 Expired - Fee Related CN1029531C (en) | 1992-12-02 | 1992-12-02 | Automatic titrimeter for measuring resistance of titration liquid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1029531C (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1086120C (en) * | 1998-12-30 | 2002-06-12 | 段成刚 | Method and device for high precision quantitive liquid (gas) supply |
| CN101975865B (en) * | 2010-10-09 | 2012-09-05 | 中国神华能源股份有限公司 | Automatic titration system for acid or alkali liquor |
| CN103901219B (en) * | 2014-03-25 | 2016-06-22 | 中国原子能科学研究院 | Suspension type gravimetric titrimetry device |
| CN104280513B (en) * | 2014-08-07 | 2016-08-24 | 湖州科诺水处理化工原料有限公司 | A kind of water sample detection reaction tank |
| CN104730202B (en) * | 2015-04-13 | 2017-01-04 | 菏泽学院 | A kind of acid alkaline titrimeter automatically |
| CN110703053B (en) * | 2019-10-23 | 2022-02-18 | 广东优科检测技术服务有限公司 | Dropping device and leakage tracking testing machine adopting same |
| CN113643958A (en) * | 2020-04-27 | 2021-11-12 | 常熟林芝电子技术有限公司 | Method for improving light distribution performance of halogen lamp filament for vehicle |
| CN113917127A (en) * | 2021-10-18 | 2022-01-11 | 安图实验仪器(郑州)有限公司 | Debugging quantification method |
-
1992
- 1992-12-02 CN CN 92113514 patent/CN1029531C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1075210A (en) | 1993-08-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Hamilton | Ion exchange chromatography of amino acids. A single column, high resolving, fully automatic procedure. | |
| CN1029531C (en) | Automatic titrimeter for measuring resistance of titration liquid | |
| US2928775A (en) | Amperometric-coulometric titration systems | |
| Bard et al. | Voltammetry retrospective. | |
| USRE32920E (en) | Electrochemical testing system and method | |
| Alexander et al. | Rapid flow analysis with inductively coupled plasma atomic-emission spectroscopy using a micro-injection technique | |
| Wang et al. | Computerized pipettes with programmable dispension | |
| US3883414A (en) | Detector of trace substance in water | |
| CN2288442Y (en) | Automatic detector for phosphate content in water | |
| Bett et al. | An automatic coulometric titrimeter | |
| CN1021413C (en) | Fully-automatic balance titrator | |
| O'Keefe et al. | Automated computer-controlled spectrophotometer system for kinetic or equilibrium methods of analysis | |
| CN1104334A (en) | Automatic potentiometric titrimeter | |
| Pungor et al. | Automatic Electrochemical Analysis: Part 2 | |
| Taylor et al. | Flow-injection coulometric titrations | |
| Arnold et al. | Automated titrations using a discontinuous programmed flow analyzer | |
| CN1554943A (en) | Method for detecting multiple heavy metal elements simultaneously | |
| US4253847A (en) | Preparing sample for electrochemical testing system | |
| US3486998A (en) | Controlled potential coulometer | |
| Uchida et al. | Application of an automatically triggered digital integrator to flame atomic-absorption spectrometry of copper using a discrete nebulisation technique | |
| CN1039303A (en) | A kind of paper tape-photometry hydrogen sulfide analyzer | |
| Rettich et al. | An inexpensive and easily constructed device for quantitative conductivity experiments | |
| CN212871354U (en) | Metering and sampling device for trace liquid | |
| CN87214257U (en) | Device for measuring chloride content in crude oil and oil products | |
| CN2363281Y (en) | Carbonate content automatic analyzer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |