Electrochemical Analysers

 

Electrochemical Analysers: Instruments, Types & Working Principles (Detailed Guide)

Electrochemical analysers are a class of composition analysers that determine the chemical

properties of substances by measuring electrical signals such as voltage, current, resistance, or charge produced during chemical reactions. These instruments are widely used in environmental monitoring, pharmaceuticals, food analysis, water treatment, and industrial process control.

They operate based on the interaction between electrical energy and chemical reactions, typically involving electrodes and electrolytes.

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🔬 1. What are Electrochemical Analysers?

Electrochemical analysers are instruments that:

• Measure chemical composition using electrical parameters

• Detect ions, gases, and compounds in solutions or gases

• Provide quantitative and qualitative analysis

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⚙️ 2. Main Working Principles

Electrochemical analysers are based on three core principles:

2.1 Potentiometry

• Measures voltage (potential difference) between electrodes

• No current flows during measurement

2.2 Amperometry

• Measures current generated by oxidation/reduction reactions

2.3 Conductometry

• Measures electrical conductivity of a solution

2.4 Coulometry

• Measures total charge passed during a reaction

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🧪 3. Types of Electrochemical Analysers & Instruments

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3.1 pH Measurement Instruments

📌 pH Meter

Principle: Potentiometry (electrode potential vs hydrogen ion concentration)

Types:

• Benchtop pH meter

• Portable pH meter

• Online/industrial pH meter

Working:

• Uses glass electrode + reference electrode

• Measures hydrogen ion activity

Applications:

• Water testing

• Pharmaceuticals

• Food industry

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3.2 Ion Measurement Instruments

📌 Ion-Selective Electrode (ISE) Analyzer

Principle: Selective ion potential measurement

Types:

• Fluoride analyzer

• Nitrate analyzer

• Sodium/Potassium analyzers

Working:

• Membrane selectively interacts with specific ions

Applications:

• Environmental monitoring

• Clinical labs

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3.3 Conductivity Measurement Instruments

📌 Conductivity Meter

Principle: Conductometry

Types:

• Bench conductivity meter

• Portable conductivity meter

• Inline conductivity sensor

Working:

• Measures ability of ions to carry current

Applications:

• Water purity testing

• Chemical industries

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📌 TDS Meter (Total Dissolved Solids)

Principle: Derived from conductivity

Applications:

• Drinking water quality

• RO systems

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3.4 Electrochemical Titration Instruments

📌 Potentiometric Titrator

Principle: Potential change during titration

Types:

• Automatic titrator

• Karl Fischer titrator

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📌 Karl Fischer Titrator

Principle: Coulometry / Volumetry

Working:

• Measures water content via iodine reaction

Applications:

• Pharmaceuticals

• Petrochemicals

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3.5 Amperometric Instruments

📌 Amperometric Analyzer

Principle: Current produced during redox reaction

Applications:

• Dissolved oxygen measurement

• Chlorine analysis

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📌 Dissolved Oxygen (DO) Meter

Principle: Amperometry

Types:

• Membrane electrode type

• Optical DO meter (advanced)

Applications:

• Wastewater treatment

• Aquaculture

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3.6 Voltammetric Instruments

📌 Voltammetry Analyzer / Potentiostat

Principle: Current vs applied voltage

Types:

• Cyclic voltammetry

• Differential pulse voltammetry

Applications:

• Trace metal analysis

• Electrochemical research

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3.7 Gas Electrochemical Analysers

📌 Electrochemical Gas Analyzer

Principle: Gas oxidation/reduction

Types:

• Oxygen analyzer

• Carbon monoxide analyzer

• Hydrogen sulfide analyzer

Applications:

• Industrial safety

• Environmental monitoring

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3.8 Corrosion Measurement Instruments

📌 Corrosion Analyzer

Principle: Electrochemical corrosion rate

Types:

• Linear polarization resistance (LPR)

• Electrochemical impedance spectroscopy (EIS)

Applications:

• Oil & gas pipelines

• Marine industry

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3.9 Biosensors (Electrochemical)

📌 Glucose Analyzer

Principle: Enzymatic electrochemical reaction

Applications:

• Medical diagnostics

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📌 Lactate Analyzer

Principle: Enzyme-based electrochemical detection

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3.10 Redox (ORP) Measurement Instruments

📌 ORP Meter (Oxidation-Reduction Potential)

Principle: Redox potential measurement

Applications:

• Water disinfection

• Swimming pools

• Chemical processes

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📊 4. Summary Table

Instrument	Principle	Measures	Applications
pH Meter	Potentiometry	Acidity	Water, pharma
ISE Analyzer	Potentiometry	Specific ions	Environment
Conductivity Meter	Conductometry	Ion concentration	Water
Titrator	Potentiometry/Coulometry	Concentration	Chemicals
DO Meter	Amperometry	Oxygen	Wastewater
Voltammetry Analyzer	Current vs voltage	Trace metals	Research
Gas Analyzer	Redox reaction	Gases	Safety
Corrosion Analyzer	Electrochemical	Corrosion rate	Oil & gas
Biosensors	Enzymatic	Biomolecules	Healthcare
ORP Meter	Redox potential	Oxidation state	Water

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🏭 5. Importance in Industries

Electrochemical analysers are essential in:

Water & Wastewater Treatment

• pH, DO, conductivity monitoring

Pharmaceuticals

• Drug formulation and quality control

Food Industry

• Quality and safety testing

Environmental Monitoring

• Pollution detection

Oil & Gas

• Corrosion and gas analysis

Healthcare

• Blood glucose and diagnostics

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✔️ Conclusion

Electrochemical analysers include a wide range of instruments such as pH meters, conductivity meters, ion-selective electrodes, titrators, and gas analysers, all based on measuring electrical signals generated during chemical interactions.

These instruments are vital for accurate, fast, and reliable chemical analysis, making them indispensable in laboratories, industries, and environmental monitoring systems.

Spectroscopic Analysers: Names

Composition Analysers: Instruments