CN107957442A - Permanganate index autotitrating method - Google Patents

Permanganate index autotitrating method Download PDF

Info

Publication number
CN107957442A
CN107957442A CN201711444876.5A CN201711444876A CN107957442A CN 107957442 A CN107957442 A CN 107957442A CN 201711444876 A CN201711444876 A CN 201711444876A CN 107957442 A CN107957442 A CN 107957442A
Authority
CN
China
Prior art keywords
titration
sample
control module
voltage
real
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.)
Pending
Application number
CN201711444876.5A
Other languages
Chinese (zh)
Inventor
陈桂淋
田倩
陈益思
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Centre Testing International Group Co ltd
Original Assignee
Centre Testing International Group Co ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Centre Testing International Group Co ltd filed Critical Centre Testing International Group Co ltd
Priority to CN201711444876.5A priority Critical patent/CN107957442A/en
Publication of CN107957442A publication Critical patent/CN107957442A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/416Systems
    • G01N27/42Measuring deposition or liberation of materials from an electrolyte; Coulometry, i.e. measuring coulomb-equivalent of material in an electrolyte

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Molecular Biology (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)

Abstract

The invention discloses a kind of permanganate index autotitrating method to include the following steps:The stoste voltage V1 of sample after resolution is recorded;Control module controls the quantitative sodium oxalate of the first syringe pump addition;The magnitude of voltage V2 of ORP electrodes output is recorded, control module calculates final voltage value automatically according to empirical equation V end=(V1-V2) * f+V2;Control module controls the second syringe pump that potassium permanganate is added dropwise by the volume of setting, is often added dropwise once, and real-time voltage value V of collection is real, when V is real<V is whole, and titration continues, and when V reality >=V terminal hours, titration stops, being often added dropwise once, and control module records a titration volumes and real-time voltage, sample tests are automatically saved in sample message table;Export voltage change in sample tests and titration process;Titration curve is drawn with voltage change in titration process, whether monitoring sample normally titrates.

Description

Permanganate index autotitrating method
Technical field
The present invention relates to the measure field of permanganate index in water, is provided in particular in a kind of both reduced and human subjective is sentenced The dependence of disconnected titration end-point, also from water sample patterns affect, the permanganate index automatic drip of raising test data accuracy Determine method.
Background technology
Permanganate index refers under certain condition, with potassium permanganate (KMnO4) it is oxidant, disappeared when handling water sample The amount of the oxidant of consumption.It is expressed as the mg/litre (O of oxygen2, mg/l).Permanganate index at the specified experimental conditions, can only Partial oxidation Organic substance in water, is not the scale for reflecting total organic content in water body.International Organization for standardization (ISO) suggests high Potassium manganate method is only limitted to measure surface water, drinking water and source water, is not suitable for industrial wastewater.
Permanganate index test principle be:The potassium permanganate and sulfuric acid of known quantity are added in sample, in boiling water bath Resolution 30 minutes, potassium permanganate aoxidize some organic matter and inorganic matter reducing substanceses in sample, are added after reaction excessive The remaining potassium permanganate of oxalic acid sodium reduction, then the sodium oxalate with potassium permanganate index solution residual titration excess is obtained by calculation Permanganate index in sample.
During the permanganate index of laboratory test at present, operating personnel judge to drip according to the change of color sample Determine terminal, the experiment qualification to operating personnel requires high.If having abnormal color after water sample muddiness or water sample resolution, even if The experimenter of skilled operation, the judgement to titration end-point also can be impacted, easily causes test result to have deviation.Therefore there is an urgent need for The automatic Titration principle of research energy accurate judgement permanganate index titration end-point, applied to permanganate index automatic Titration system System.
Therefore, there is an urgent need for a kind of both reduced to judge human subjective the dependence of titration end-point, also from water sample patterns affect, Improve the permanganate index autotitrating method of test data accuracy.
The content of the invention
The object of the present invention is to provide a kind of both reduced to judge human subjective the dependence of titration end-point, also from water sample Patterns affect, improves the permanganate index autotitrating method of test data accuracy.
To achieve these goals, technical solution provided by the invention is:A kind of permanganate index automatic Titration is provided Method, there is provided:Host computer, control module, the first syringe pump, the second syringe pump, ORP electrodes, sodium oxalate, potassium permanganate, sulfuric acid, Include the following steps:
(1) sample is added into the potassium permanganate of known quantity and sulfuric acid is cleared up, the sample for clearing up completion is placed in titration Position, is inserted into Suitable depth in sample by ORP electrodes, after control module receives the control signal of seat in the plane, automatically begins to titrate, The stoste voltage V1 of ORP electrodes output is recorded;
(2) control module controls the quantitative sodium oxalate of the first syringe pump addition;
(3) after sodium oxalate and potassium permanganate fully react, the magnitude of voltage V2 of record ORP electrodes output at this time, controls mould Block calculates final voltage value automatically according to empirical equation V end=(V1-V2) * f+V2, and wherein correction coefficient f is determined before testing Good and input control module, titration end-point is captured for precise control;
(4) control module controls the second syringe pump that potassium permanganate is added dropwise by the volume of setting, is often added dropwise once, collection one Secondary real-time voltage value V is real, when V is real<V is whole, and titration continues, and when V reality >=V terminal hours, titration stops, being often added dropwise once, controls Module records a titration volumes and real-time voltage, and after the completion of titration, sample tests are automatically saved in sample message table;
(5) voltage change in sample tests and titration process is exported;
(6) voltage change in titration process is used to draw titration curve, whether monitoring sample normally titrates, if curve light It is sliding without fluctuation, it is and consistent with normal titration curve trend, judge that the automatic test result of the sample is normal, if curve is rough and ripple It is dynamic bigger, then judge that the automatic test result of the sample is abnormal.
Compared with prior art, the beneficial effects of the invention are as follows:
(1) rule of thumb formula V end=(V1-V2) * f+V2 calculate final voltage value, and V1, V2 are real-time voltage value, It is not required to gather for a long time, simplifies the process for determining that titration terminates ORP value, dynamic control titration end-point, substantially increases terminal The flexibility of judgement.
(2) it is not a fixed value that correction coefficient, which is variable, different manufacturers, the adjusted school of ORP electrodes of different model After positive coefficient, you can adapt to the titration system, the applicable electrode of the titration system is not limited to certain a special electrodes.
(3) it is not required to calibrate electrode after replacing ORP electrodes, correction coefficient need to be only adjusted according to titration situation It is whole, you can to ensure titration end-point accurate judgement.
(4) to occurring the water sample of abnormal color after turbid water sample and resolution, titration method provided by the invention can accurately be known Other titration end-point, from the influence of sample state.
It will be become more fully apparent by following description and with reference to attached drawing, the present invention, these attached drawings are used to explain the present invention Embodiment.
Brief description of the drawings
Fig. 1 is the schematic diagram of permanganate index automatic Titration system.
Fig. 2 is expressed as the schematic diagram of the titration curve of permanganate index autotitrating method of the present invention.
Embodiment
The embodiment of the present invention described referring now to attached drawing, similar element numbers represent similar element in attached drawing.Such as Upper described, as illustrated in fig. 1 and 2, permanganate index autotitrating method of the present invention is to be based on permanganate index automatic Titration What system was realized.
As shown in Figure 1, permanganate index automatic Titration system is made of three parts, it is respectively control module, syringe pump With ORP electrodes.Control module be used for titration system control, including control syringe pump action, gather ORP electrodes voltage, Titration end-point is judged etc.;Syringe pump has two, is respectively used to the dropwise addition of liquor potassic permanganate and sodium oxalate solution;ORP Electrode is used for the real-time change for catching voltage in titration process.
Permanganate index autotitrating method of the present invention is introduced with reference to Fig. 2, wherein:Abscissa is to be consumed in titration process Permanganate solution volume, ordinate is the magnitude of voltage that electrode exports in titration process, when real-time electricity Ya≤V terminal hours, titration Stop.
(1) sample is added into the potassium permanganate of known quantity and sulfuric acid is cleared up, the sample for clearing up completion is placed in titration Position, ORP electrodes are inserted into Suitable depth in sample, after control module receives the control signal of seat in the plane, automatically begin to titrate, right The stoste voltage V1 of ORP electrodes output is recorded;
(2) control module controls the quantitative sodium oxalate of the first syringe pump addition;
(3) after sodium oxalate and potassium permanganate fully react, the magnitude of voltage V2 of record ORP electrodes output at this time, controls mould Block calculates final voltage value automatically according to empirical equation V end=(V1-V2) * f+V2, and wherein correction coefficient f is determined before testing Good and input control module, titration end-point is captured for precise control;It should be noted that the determination process of correction coefficient f: Larger coefficient is inputted in control module, is put into the sample cleared up, automatically begins to titrate, after the completion of titration, export titrated The magnitude of voltage exported in journey, draws titration curve, liquor potassic permanganate is being added dropwise in titration curve with magnitude of voltage and titration volumes During trend that is smooth and being declined slightly is presented, be titration end-point when curve is in mutation trend is risen, obtain electric at this time Pressure value, rule of thumb formula, with reference to the stoste magnitude of voltage V1 and magnitude of voltage V2 for adding sodium oxalate, can be calculated correction coefficient f.
(4) control module controls the second syringe pump that potassium permanganate is added dropwise by the volume of setting, is often added dropwise once, collection one Secondary real-time voltage value V is real, when V is real<V is whole, and titration continues, and when V reality >=V terminal hours, titration stops, being often added dropwise once, controls Module records a titration volumes and real-time voltage, and after the completion of titration, sample tests are automatically saved in sample message table;
(5) voltage change in sample tests and titration process is exported;
(6) voltage change in titration process is used to draw titration curve, whether monitoring sample normally titrates, if curve light It is sliding that without fluctuation, and consistent with normal titration curve trend, the automatic test result of the judgement sample is normal, if curve it is rough and Fluctuate bigger, then judge that the automatic test result of the sample is abnormal.
It should be noted that how many sodium oxalate added every time, it is well known to those skilled in the art and has standard to look into 's.
The first syringe pump and the second syringe pump are introduced, the present invention uses two syringe pumps, and the first syringe pump is used to drip Add sodium oxalate solution, the second syringe pump is used to liquor potassic permanganate be added dropwise.Each syringe pump pump is respectively connected with two valve positions, is denoted as A and B, wherein the valve position A of the first syringe pump and the second syringe pump is all connected with reagent bottle, i.e., as shown in Figure 1, two pumps connect respectively Sodium oxalate solution and liquor potassic permanganate, B connection sample bottles.
In addition, the particular technique index that syringe pump uses is as follows:
1st, liquid measure accuracy:Error≤1% (during rated travel);
2nd, liquid measure accuracy:Repeatability error≤0.5% (during rated travel);
3rd, rated travel (control step number):60mm (6000 step);
4th, linear velocity scope:0.05mm/s-50mm/s;
5th, rated travel run time scope:1.2s-1200s;
6th, control resolution:0.01mm (1 step);
7th, drive mechanism:Ball-screw-transmission;
8th, piston maximum driving force:≥60N;
9th, piston secondary drive power:≥34N;
10th, using specification of syringe:50 μ L, 100 μ L, 250 μ L, 500 μ L, 1mL, 2.5mL, 5mL, 10mL, 25mL (this hair Bright embodiment uses 10mL syringes);
11st, valve-type:Standard configuration:3 mouthfuls of 120 ° of valves, may customize:4 mouthfuls of 90 ° of valves, T-shaped 90 ° of valves, 90 ° of distributing valves;
12nd, the valve transposition time:≤ 280ms (adjacent between two mouthfuls);
13rd, fluid path material:Borosilicate glass, polytetrafluoroethylene (PTFE), polytrifluorochloroethylene;
14th, fluid path maximum pressure-bearing reference value:0.68Mpa;
15th, pipe interface:1/4 " -28 internal thread interface;
16th, syringe interface:1/4 " -28 internal thread interface;
17th, signal inputs:2 road Transistor-Transistor Logic level signal inputs (driving current > 16mA), after controlling static pause instruction Restarting;
18th, signal output:3 road OC gate signals outputs, for indicating operating status;
19th, communication interface:RS485/RS232 can be set;
20th, traffic rate:9600bps/38400bps can be set;
21st, device parameter is set:6 DIP toggle switch (communication interface, communication speed etc.);
22nd, appearance and size (length × width × height):114×65×254(mm);
23rd, it is applicable in power supply:DC 24V/1.5A;
24th, operating ambient temperature:15 DEG C -40 DEG C (mainly the temperature characterisitic of polytetrafluoroethylene material is determined in by syringe It is fixed);
25th, working environment relative humidity:< 80%;
26th, weight:2.15kg.
ORP electrodes are introduced, the height of ORP electrodes need to be adjusted according to liquid level in sample bottle, ensure platinum Ring is soaked in solution.ORP electrodes should be soaked in 3.3M KCl solution when not in use.ORP standards can be used molten when first used Liquid is corrected electrode.
The particular technique parameter of ORP electrodes is as follows:
1st, ORP testing ranges:±5000mV;
2nd, Applicable temperature scope:0-100℃;
3rd, electrode is pressure-resistant:It is up to 50PSI;
4th, effective measurement region of electrode:Platinum ring (99.99%), the L of 0.25 " O.D. × 0.1 ";
5th, reference system:The double salt bridge designs of Ag/AgCl;
6th, with reference to filling liquid:3.3M (KCl) not refilling type (inner presseds);
7th, liquid connects material:Glass, platinum and ceramics.
It should be noted that the spare and accessory parts such as syringe pump, syringe, triple valve, ORP electrodes disclosed in the embodiment of the present invention Concrete model or technical parameter, be all a kind of combination in numerous embodiments, the power of the present invention can not be limited with this The protection domain that profit requires, can also select the spare and accessory parts of other models to be combined as needed in practical application, still belong to this The covered scope of invention.

Claims (1)

1. a kind of permanganate index autotitrating method, it is characterised in that provide:Host computer, control module, the first injection Pump, the second syringe pump, ORP electrodes, sodium oxalate, potassium permanganate, sulfuric acid, include the following steps:
(1) sample is added into the potassium permanganate of known quantity and sulfuric acid is cleared up, the sample for clearing up completion is placed in titration position, ORP electrodes are inserted into Suitable depth in sample, after control module receives the control signal of seat in the plane, automatically begin to titrate, it is right The stoste voltage V1 of ORP electrodes output is recorded;
(2) control module controls the quantitative sodium oxalate of the first syringe pump addition;
(3) after sodium oxalate and potassium permanganate fully react, the magnitude of voltage V2 of record ORP electrodes output at this time, control module is certainly Dynamic rule of thumb formula V end=(V1-V2) * f+V2 calculate final voltage value, and wherein correction coefficient f is determined simultaneously before testing Input control module, titration end-point is captured for precise control;
(4) control module controls the second syringe pump that potassium permanganate is added dropwise by the volume of setting, is often added dropwise once, and collection is once real When magnitude of voltage V it is real, when V is real<V is whole, and titration continues, and when V reality >=V terminal hours, titration stops, being often added dropwise once, control module A titration volumes and real-time voltage are recorded, after the completion of titration, sample tests are automatically saved in sample message table;
(5) voltage change in sample tests and titration process is exported;
(6) use titration process in voltage change draw titration curve, monitoring sample whether normally titrate, if line smoothing without Fluctuation, and it is consistent with normal titration curve trend, the automatic test result of the judgement sample is normal, if curve is rough and fluctuates It is bigger, then judge that the automatic test result of the sample is abnormal.
CN201711444876.5A 2017-12-27 2017-12-27 Permanganate index autotitrating method Pending CN107957442A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201711444876.5A CN107957442A (en) 2017-12-27 2017-12-27 Permanganate index autotitrating method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201711444876.5A CN107957442A (en) 2017-12-27 2017-12-27 Permanganate index autotitrating method

Publications (1)

Publication Number Publication Date
CN107957442A true CN107957442A (en) 2018-04-24

Family

ID=61955903

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201711444876.5A Pending CN107957442A (en) 2017-12-27 2017-12-27 Permanganate index autotitrating method

Country Status (1)

Country Link
CN (1) CN107957442A (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201159728Y (en) * 2007-11-12 2008-12-03 江苏绿叶环保科技仪器有限公司 Automatic detection instrument for permanganate index
CN201780281U (en) * 2010-08-31 2011-03-30 宇星科技发展(深圳)有限公司 Online water quality analyzer for permanganate index
JP2011183305A (en) * 2010-03-09 2011-09-22 Taiheiyo Cement Corp Method of treating incineration ash
CN102288667A (en) * 2011-05-06 2011-12-21 厦门隆力德环境技术开发有限公司 Titration endpoint determination method for ORP (oxidation-reduction potential) value of permanganate index type water quality analyzer

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201159728Y (en) * 2007-11-12 2008-12-03 江苏绿叶环保科技仪器有限公司 Automatic detection instrument for permanganate index
JP2011183305A (en) * 2010-03-09 2011-09-22 Taiheiyo Cement Corp Method of treating incineration ash
CN201780281U (en) * 2010-08-31 2011-03-30 宇星科技发展(深圳)有限公司 Online water quality analyzer for permanganate index
CN102288667A (en) * 2011-05-06 2011-12-21 厦门隆力德环境技术开发有限公司 Titration endpoint determination method for ORP (oxidation-reduction potential) value of permanganate index type water quality analyzer

Similar Documents

Publication Publication Date Title
CN101788522B (en) Chemical oxygen demand (COD) on-line monitoring device and method based on boron-doped diamond membrane electrode
CN103499373B (en) Be with self-alignment automatic capacity calibration device for tank truck and method
CN109557247B (en) Hydrolysis degree measuring instrument and measuring method thereof
CN102680721A (en) COD (chemical oxygen demand) online monitoring instrument
CN207650174U (en) Permanganate index automatic titration system
CN110346509A (en) A kind of online permanganate index monitor of water quality and detection method
CN107894489A (en) permanganate index automatic titration system
CN203941128U (en) The device of contents of residual chlorine in a kind of on-line measurement tap water
CN107957442A (en) Permanganate index autotitrating method
CN205333150U (en) A jar liquid level warning device is weighed in pitch storage
CN111103338A (en) Multi-mode automatic pH measuring instrument based on network and measuring method thereof
CN107064223B (en) Online measurement and calibration system and method adopting intelligent trace dissolved oxygen analyzer
CN203299161U (en) Multifunctional tin plate surface property testing device
CN207248817U (en) For measuring the automatic Titration potentiometer of chemical plating fluid stability
CN207717726U (en) A kind of automatic titration device
CN116067957B (en) Device and method for online water quality monitoring
CN210465367U (en) Water quality on-line permanganate index monitor
CN209372750U (en) Seawater permanganate index analysis system
CN113514601A (en) Permanganate index online detection method and system
CN203572812U (en) Device for measuring concentration of sulfur dioxide at outlet of converter during production of sulfuric acid
CN104034760A (en) Multifunctional tin plate surface characteristic testing device and use method thereof
CN201392283Y (en) Novel quantitative sampler
CN205478256U (en) Flow detection device of measuring pump
CN213063544U (en) Rock core displacement device that surplus oil saturation detected
CN103901082B (en) Tin plate sheet surface chromium amount electrolysis self-operated measuring unit and mensuration endpoint method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20180424

WD01 Invention patent application deemed withdrawn after publication