Comparative ph-electrode |
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IPC classes for russian patent Comparative ph-electrode (RU 2127427):
 Electrochemical sensor for measuring the concentration of gases and the method of determining the concentration of gases by means of the sensor / 2106621
The invention relates to an electrochemical sensor for determining the concentration of a gas, comprising a housing, a measuring electrode containing a catalytically active material that has the ability to cause transformation of the sample gas, a counter-electrode containing a carbon material with the electrochemically active surface compounds that can reversibly oxidize, or to recover, and an electrolyte in contact with the measuring electrode and counter-electrode, while the carbon material in the counter-electrode has a specific surface area of at least 40 m2/g
 Composite solid electrolyte for electrochemical sensors partial pressure of sulfur oxides / 2095800
The invention relates to analytical instrumentation and relates to a solid electrolyte for electrochemical sensors partial pressure of sulfur oxides
 Device for measuring the partial pressure of oxygen and the method of its manufacture / 2092827
The invention relates to the field of gas analysis, in particular, to a device for measuring the partial pressure of oxygen, containing a solid electrolyte and electrodes connected to the terminals for the signal is removed, the solid electrolyte is an oxide film of the material of the first electrode, in the form of metal matrix and placed inside the oxide film, the first outlet for removal of the signal connected to the metal matrix in the topic area, metal oxide, the second electrode is located on the surface of the oxide film and is made in the form permeable to oxygen conductive layer
 A device for gas analysis / 2091783
The invention relates to a device for gas analysis using electrochemical cells with solid electrolyte and can be used for control and regulation of process of burning all types of fuel
 Method of manufacturing electrode / 2029946
The invention relates to the field of gas analysis and gas-analyzing instrument engineering, in particular to the technology of fabrication of electrodes on the solid electrolyte of stabilized Zirconia, and can be used in the manufacture of electrochemical solid electrolyte sensor of oxygen concentration in various oxygen-containing gases, such as flue gases of power plants, the exhaust gases of internal combustion engines and so on
 The method of manufacture of the modified electrode for stripping voltammetric method for determination of traces of heavy metals and toxic / 2124720
The invention relates to the field of electrochemical methods of analysis, in particular for the determination of heavy metals using modified electrode
 Universal combined ion-selective sensor (options) / 2117281
The invention relates to a device for controlling the ionic composition and properties of technological solutions, natural and waste waters and may find wide application in chemical, food, pulp and paper, mining industry, energy, biotechnology, medicine, ecology, Geology, as well as when conducting high-altitude aerospace and deep hydrological studies
 Multiple microelectrode and the method of its manufacture / 2112966
The invention relates to measurement techniques, in particular to measure the concentration of inorganic and organic compounds in various objects
 Device for electrochemical measurements (options) / 2097754
The invention relates to the field of electrochemical measurements, namely the device for electrochemical measurements (options)
The sensor for the analysis of gaseous substances / 2088914
The invention relates to measuring equipment
 Film multiple microelectrode / 2078337
 Electrode system for voltammetric analysis / 2061229
The invention relates to means voltammetric methods of analysis and can be used to study the composition of organic and inorganic substances, medical and other objects
 Method of manufacturing electrode for voltammetric measurements / 2039975
The invention relates to the technology of solid electrodes for electrochemical cells.The inventive method consists in ensuring the constancy of the area of the working surface of the electrode
 Reference electrode / 2247366
Device can be used for testing natural water and any water-containing mixtures in open pools and wells at any depth (at the bottom of pools, in vertical, horizontal, inclined wells including well with negative inclination), for precision monitoring ion solutions, especially at high pressures and temperatures. Reference electrode has case with hole to fill the electrode and at least one liquid communication. Case is made waterproof. Active element is disposed inside the case, active element is connected with electric input. Auxiliary vessel is connected with case of electrode by means of pipe which has one end connected with side of auxiliary vessel being close to the case. The other end is disposed at the same level hole for filling case in.
 Composite material for environmental monitoring sensors / 2257568
Invention relates to electrochemical analytical methods, in particular to structure and a method for manufacturing potentiometric electrodes. Composite electrode is preferably used in production and environmental water control (aqueous solutions) for level of cuprous ions. Base for sensitive element of sensor composite is conductive metal-polymer composite containing superfine copper particles in polymer matrix, which is made by chemical reduction-mediated deposition of superfine copper particles on the surface of dispersed particles of thermoplastic polymer followed by hot compaction.
 Membrane solion / 2260796
Membrane solion can be used as for dense and micro-pore membrane. Device has case filled with internal solution, indicator electrode, separating membrane and tool for fixing membrane. Elastic member provided with holes is installed between separating membrane and tool for fixing membrane. Internal surface of elastic member follows external surface of indicator electrode. Diameters of holes in elastic member 200 times max exceed thickness of separating membrane. Holes in elastic member can have random shape. Sizes of holes along their minimal axes do not have to exceed thickness of separating membrane 200 times max.
 Electrode / 2319954
Electrode comprises insulated housing filled with electrolyte, rod mounted inside the housing, potential pickup mounted on the housing and connected with a tip, and ion-exchange diaphragm. The rod is made of silver and represents an electrode. The ion-exchanger diaphragm is pressed to the housing via the sealing spacer by means of clutch provided with perforation. The electrolyte is made of the saturated water solution of a mixture of potassium chloride and ethylene glycol in a ratio of 3:2-2:1.
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(57) Abstract: The invention relates to a potentiometric measuring ion concentrations in solutions, namely the comparative pH-electrode, comprising a housing situated in the body of the electrolyte, an ion-conductive membrane separating the electrolyte and the environment, and placed in the electrolyte sensing element, while the electrolyte in the form of hydrated NH4Ca(NO3)3nH2O received by the exchange reaction Ca(OH)2with a saturated solution of NH4NO3. 2 C.p. f-crystals, 1 Il. The invention relates to a potentiometric measuring ion concentrations in solutions, namely the comparative electrode for receiving the reference potential comparison of a constant with time according to the value in measuring pH. There are two types of comparative electrodes is stagnant and flowing ([1], S. 26, 27). Stagnant comparative electrode includes a housing (glass tube) located in the housing, the electrolyte (solution of silver chloride and placed in the electrolyte sensing element (silver contact electrode), as well as the separation is not conductive solution ions rubber membrane DL is traitor, fill the inner cavity of the electrode is on the surface of the glass, matted in places adhesion to a rubber membrane ([1], S. 26, Fig. 12). Running comparative electrode includes a housing (receptacle) located in the housing, the electrolyte (solution of potassium chloride and placed in the electrolyte sensing element (hlorserebryany electrode), while the electrical contact between the test environment and the electrolyte that fills the inner cavity of the electrode, through the electrolyte, which under the action of gravity is slowly poured in a controlled solution through the tube and the tip is fitted with a gasket made of porous material ([1], Fig. 13). Stagnant electrode is sufficiently reliable in operation and simple in operation, however, has a relatively unstable potential due to the possibility of passing ions controlled environment in the electrolyte of the electrode. The flow-through electrode has a high degree of stability potential, as its potential is almost independent from the controlled environment and there is little change when the ambient temperature. However, he has a complicated operation: depends on atmospheric pressure and treemenu is hlorserebryany comparative electrode of the industrial type C-15.684.05, produced Gomel plant spare parts, which includes a housing located in the housing, the electrolyte (crystalline silver chloride and placed in the electrolyte sensing element (silver rod, the surface of which is deposited a layer of AgCl is less soluble salts), and an ion-conductive membrane for the separation of the electrolyte and the studied environment ([1], S. 21, Fig. 8 - prototype). The listed signs of the prototype is common with the claimed invention. Obstacle getting in the known technical solutions required technical result, it is impossible to specify, because the claimed invention is directed to expanding Arsenal of technical means for a specific purpose. The invention is directed to solving the problem of expanding Arsenal of technical means for potentiometric measurements. The technical result, the mediating solve this problem, is to implement the specified destination. This technical result is achieved by the fact that in the comparative electrode for potentiometric measurements, comprising a housing situated in the body of the electrolyte, an ion-conductive membrane separating aleida of crystalline NH4Ca(NO3)3nH2O received by the exchange reaction Ca(OH)2with a saturated solution of NH4NO3;the sensing element is made of corrosion-resistant insoluble in acid and alkali metal stamps EI-943; an ion-conductive membrane made of high-temperature pranita; the body is made of metal with ground. The drawing shows a General view of the inventive comparative electrode for potentiometric measurements. The electrode contains lead wire 1, the gasket 2, the cap 3, the sensing element 4, the solid electrolyte 5 in the form of hydrated NH4Ca(NO3)3nH2O, the insulator 6, the metal case 7, the cap nut 8 with an axial hole, an ion-conductive membrane 9. Lead wire connected to the sensor element 4 and is designed to connect the electrode to the measuring instrument. The cap 3 and the insulator 6 provide electrical isolation of the solid electrolyte 5 from the metal housing 7 made of cylindrical metal ground lug from the influence of external magnetic fields. The cap 3 and cap nut 8 ensure the manufacturability of the Assembly of the electrode, and coupling gillego or less compression between the said nut 8, on the one hand, and the end surface of the solid electrolyte 5, the insulator 6 and the housing 7, on the other hand. A saturated solution of ammonium nitrate NH4NO3in the ratio of one-to-one is mixed with powder of slaked lime Ca(OH)2and the resulting mixture is placed in a housing 7. Slaked lime is produced by the method of time-keeping outdoors calcium carbide. In this case, the partial dissolution of calcium carbide by the reaction equation CaC2+2H2O=C2H2+Ca(OH)2< / BR> to the slaked lime is under the influence of moisture contained in the air. When this powder calcium carbide takes the form suitable to the manufacture of the electrolyte, as a component of the mixture. Later in the powder pour the solution, mix the powder until it is fully moisturized and only after that the mixture is placed in the cavity of the housing 7, which is continuously putting its seal. For a more complete electrical contact between the electrolyte and paranitovye membrane placed impregnated with the mixture and rolled in a double ring cord from a material that is prone to swelling, particularly asbestos. Thereafter, the casing 7 is screwed cap nut 8 with such facilities the MENA Ca(OH)2with a saturated solution of ammonium nitrate NH4NO3in the cavity of the housing 7, the following happens: -2NH4NO3+Ca(OH)2=Ca(NO3)2+NH4OH+NH3+nH2O; -NH4NO3+CA(NO3)2+H2O= NH4Ca(NO3)nH2O. Where the overall reaction process is as follows: CaC2+NH4NO3+Ca(NO3)2+ 3H2O=C2H2+NH4Ca(NO3)3nH2O it gradually hardens to a solid state; Ca(OH)2- the remains of slaked lime; - NH4OH - hydroxide ammonium (electrolyte in aqueous solutions). In the end, the sensing element 4 becomes a potential whose magnitude is a function of the activity of ions in NH+4and NO-3. In this case, the electrical contact between the solid electrolyte 5 controlled environment is carried out through the membrane 9 from paramita, while performing the role of the impediments to the diffusion of the ions NH+4and NO-3in a controlled environment. Electrical contact is through the hole in the center of the cap nut 8. Furthermore, formed in rezultatele intermediate product the ammonium hydroxide NH4OH. Due to weak ionic dissociation (dissociation constant K = 1,7910-5) ions NH+4and OH-created maloprodaja environment in the solid electrolyte 5, which allows to maintain the electrode potential on the sensing element 4 in a stable state for a long time due to the small ionization current in the circuit: the sensing element 4 is the solid electrolyte 5 - controlled environment. An overview of the development of technical solutions to create a comparative electrode shows: all sensitive elements are made, usually from the same metal, which in all cases when it is placed in the electrolyte on the surface flows of the redox reaction. Thus in practice the use of metals as sensitive elements, it was found that due to insufficient electrical attraction on its surface between the metal and the ions of the electrolyte solution even with his weak mixing the ionic equilibrium of the redox reaction is disturbed. And only steady-state solution after a long period of electric potential is otherwise change the concentration of ions in the near-electrode space of the formation of the electric potential and as a result, changing the value of its value. In this case, the technical problem to obtain a stable electric potential, as the author believes, is solved as follows: for example, for a sensor element made of platinum, the latter is covered melkorazdroblennuyu spongy platinum (platinum black), which, as stated in [2], thus greatly increasing the surface of contact of the metal with hydrogen. In this case, the author believes that by increasing the contact area of the passage redox reaction increases the total power of the electric potential, which ultimately has a positive impact on the effect of the manifestations of the forces of mutual stretch: metal-ion H+. The presence of spongy platinum allows, moreover, to obtain additional positive effect: a small dependence on mixing the solution. This, according to the author, perhaps because filling the voids between the particles of platinum mobile ions due to their deep penetration sedentary. However, as noted in [2], the value of the building has a significant impact gas pressure, causing the oscillation conc the STATCOM, compensated flow control of gas pressure, allowed to obtain the effect of creating a normal hydrogen electrode taken as a comparative (reference) electrode. The sensing element in the claimed invention is made of corrosion-resistant, well sanded, no reacts with acids and alkalis high-alloy metal, for example, the brand of EI-943 [3]. This metal is an alloy of iron-Nickel-based 7-6 class corrosion resistance GOST 5632-72 and consists of the following components: OHMZ, where X - Chrome = 23%; N - Ni = 28; M - mo = 3%; Dr. Copper = 3%; T - Titanium < 1%. According to the data [4], if corrosion steel contains up to 12% chromium, upon reaching a given concentration of chromium in iron-based alloys, abruptly increasing the electrochemical potential and the steel goes into the category of corrosion-resistant. As practice shows observations of the work of the comparative electrode having such sensitive element, the slope of working with him in the control system of the measuring electrode retains a constant value of 58 mV/pH, during the whole time, u is the penalty meets the Metrology standard maintain its electric potential in time. Compared with earlier types of comparative electrodes: he doesn't need a continuous supply of gas NH+4because NH4OH in the pores of the crystalline distributed evenly and has excess concentration, due to the complete "wetting" of slaked lime in a closed facility; the presence of crystalline acetylene in the gaseous state ensures the safety of its porosity; because the stability of the electric potential of the comparative electrode and the formation of its size, is largely dominated by the adhesive interaction between the metal surface with the solid electrolyte, the metal should not have any coverings, and requires polishing to a mirror finish; given a uniform distribution in the amount of hydrated NH4OH, impurities having the same distribution, largely influenced by the value of electric potential, but not its stability in contrast to the electrolyte with an admixture in liquid form; - distributed in the pores of the hydrated in the presence of moisture NH4OH behaves as a buffer solution with a pH of 8.3 to 9.2 [5], like the buffer NH4Cl (ammonium chloride). the value from the conditions: - salt effect; effect of dilution; - change the value paHthe temperature of the electrolyte. Moreover, according to the author, crystallohydrate structure of the electrolyte will not create the possibility of their occurrence. Essential for this type of declared electrode is that the constant presence of an excess of acetylene gas in a confined space crystallohydrates electrolyte, causes a positive effect of counter-penetration of the electrolyte ions monitored solution. Comparative electrode operates as follows. A saturated solution of ammonium nitrate NH4NO3mixed with powder of slaked lime Ca(OH)2to complete "wetting" (i.e., the solution of ammonium nitrate NH4NO3comes with some excess) and the resulting mixture is placed in a housing 7 in which the exchange reaction according to the equation: 2NH4NO3+ Ca(OH)2= Ca(NO3)2+ NH4OH + NH3+ nH2O H2O + NH4NO3+ Ca(NO3)2= NH4Ca(NO3)3nH2O After the reaction in the housing 7 of the comparative electrode is formed hydrated NH4+4Ca+2and NO-3. In this case, the electrical contact between the solid electrolyte 5 controlled environment is carried out through the membrane 9 from paramita, while performing the role of the impediments to the diffusion of the ions NH+4and NO-3in a controlled environment. Electrical contact is through the hole in the center of the cap nut 8. In addition, resulting from the reaction of ammonia H3connected with the part available in solid electrolyte water. This results in the ammonium hydroxide NH4OH, which has an ionization constant of Ki = 1,79 10-5. Due to weak ionic desocialization NH4OH ions NH+4and OH-created maloprodaja alkaline environment in the solid electrolyte 5, which allows to maintain the electrode potential on the sensing element 4 in a stable state for a long time. Technical data. 1. The temperature of the analyzed medium -40 to 150oC 2. The pressure of the analyzed medium to 1.4 MPa. 3. Potential comparative electrode < / BR> 4. Internal resistance to high reliability in all environments, especially in environments containing Floriani, suspension and mechanical impurities. Does not require any real maintenance. The electrolyte provides the use of comparative electrodes in the temperature range from minus 40 to plus 150oC. in Addition, the electrode can be used for measurements in tanks and pipelines under high pressure intensively peremeshivayte liquids, and also in conditions of strong electromagnetic fields. Literary sources 1. Potentiometric and titrimetrically devices. Kantere C. M., Kazakov, A. C., M. Kulakov Century: engineering, 1969, 308 S. 2. A. G. Coleman. General chemistry. M: Agricultural. lit., 1961, S. 300, 301. 3. C. M. Raskatov. Engineering materials. Quick reference. M: mechanical engineering, 1980, S. 54, p. 7. 4. B. M. Arsamakov. Structural materials. The Handbook. M: mechanical engineering, 1990, S. 380. 5. R. Bates. Determination of pH, theory and practice. L.: Chemistry, ed. 2nd, 1972, S. 115. 1. Comparative pH-electrode for potentiometric measurements, comprising a housing situated in the body of the electrolyte, an ion-conductive membrane separating the electrolyte and the environment, and placed in the electrolyte feelings/SUB>nH2O received by the exchange reaction Ca(OH)2with a saturated solution of NH4NO3. 2. pH-electrode under item 1, characterized in that an ion-conductive membrane made of high-temperature paronite, and the body is made of metal with ground. 3. pH electrode p. 1, wherein the sensitive element is made of stainless thoroughly polished, not reacts with acids and alkalis alloyed metal.
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