LABORATORIES \ ELECTROCHEMICAL ANALYSIS

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ELECTROCHEMICAL ANALYSIS LABORATORY

 

 ANALYSIS TECHNIQUES
 
 


Brief description of laboratory activity. TOP

Electrochemistry is a branch of physical chemistry that studies ion containing systems (solutions and electrolyte melts), as well as the processes that take place at the phase separation surfaces in the presence of charged particles – ions and electrons. Electrochemistry can also be defined as the science that examines the interaction of the metal or semiconductor charges with the solution ions and solution molecules or with the ions in melts. In some cases such interactions are accompanied by the appearance of electric current in the electric circuit. In this case, electrochemistry can be defined as the science that studies physico-chemical processes, accompanied by the appearance of electric current or the influence of electric current on the chemical compounds.

The experiments undertaken in our scientific laboratory comprise:

Analytical and characterization methods used in our laboratory TOP

PGZ – 301 Universal Potentiostat
TOP

Manufacturer: Radiometer Copenhagen

Technical properties:

VoltaLab 40 consists of a PGZ301 Potentiostat plus VoltaMaster 4 Electrochemical Software and a set of cables. The PGZ301 Potentiostat is a dynamic system which combines outstanding performance and ease of use. It represents a major breakthrough in the field of ohmic drop compensation by offering dynamic compensation controlled by impedance measurement. It is the obvious choice for high-level researchers. It is the easiest to use and most versatile "all-in-one" potentiostat on the market and it is ideal for Electrochemical Impedance Spectroscopy combined with conventional methods such as Voltammetry.

  • Maximum compliance voltage                              ±30 V
  • Maximum current output                                      ±1 A
  • Maximum polarization voltage                             ±15 V
  • Measured current best resolution                          30 pA
  • Measured potential best resolution                       60 µV
    Scanning performance                                      
  • Measurement period                                             500 µs
  • Max. scan rate                                                       20 V/s
    Electrochemical Impedance                              
  • Max. frequency                                                     100 kHz
  • Min. frequency                                                      1 mHz
    Ohmic Drop Compensation                              
  • Dynamic Impedance Driven                                 up to 100 mV/s
  • Static manual & Static auto                                  up to 1 V/s
  • Feedback manual & Feedback auto                      up to 20 V/s

Uses and accessories:
This apparatus allows several methods of analysis: chronopotentiometry, chronoamperometry, voltammetry i=f(E) and E=f(i), Evans diagrams, corrosion, stationary voltammetry, impedance studies and making of analysis techniques for electrode electroactivity. Allows the determination of the corrosion speed by electrochemical approach. This method is based on the direct correlation between the current measured at the electrodes and the amount of metal transferred in the corrosive environment. The apparatus allows the determination of the optimal conditions in case of electrochemical surface coatings.

The accessories of the apparatus are: BEC/EDI X51 V001 electrochemical cell with electrodes (graphite, platinum, steel, copper, ruthenium, molybdenum, glassy carbon, cantal, silver, gold, calomel, iron, tantalum, niobium) and a set of cables.

Properties of analyzed samples
In the case of cyclical voltammetry, before immersing the electrodes in the electrolyte solution, they must undergo the following stages:

  • electrode grinding with sand-paper until a smooth and glossy surface can be observed
  • ultrasonication
  • washing with distilled water
  • immersion in electrolyte solution

The properties of the electrolyte solution vary according to the experiment.

Results:
From voltammograms one can determine the reduction-oxidation properties of the process at hand.  The reading of the results depends on the current density values and those of the electrochemycal potential.

Short description of the technique:
PGZ301 Universal Potentiostat allows the determination of the optimum conditions in case of electrochemical surface coverage (metal depositions, conversion coatings). It is ideal for Electrochemical Impedance Spectroscopy combined with conventional methods such as Voltammetry.

Services:
This apparatus allows several methods of analysis: chronopotentiometry, chronoamperometry, voltammetry i=f(E) and E=f(i), Evans diagrams, corrosion, stationary voltammetry, impedance studies and making of analysis techniques for electrode electroactivity. It allows the determination of the corrosion speed by electrochemical approach and the determination of the optimal conditions in case of electrochemical surface coatings.

Contact:
Person responsible for device:

 

TITRALAB TIM 845
TOP

Manufacturer: Agilent Technologies - Germany

Year: 2007

Technical properties

With the new multi-technique TitraLab 845 bi-burette titration workstation you can benefit from superior quality results at the touch of a button. Ideal for routine applications, its use is simpler than ever before. The TitraLab 845 represents today the best value for money on the market for routine potentiometric titrations, whatever your application.

Environmental conditions: 5 to 40°C ambient temperature, 20 to 80% relative humidity

  • pH-meter: 
    • 9...23pH, resolution 0,001 pH
    • 2000....+2000, resolution 0,1 mv
    • 10oC.....+ 100oC, resolution 0,1 oC

accessories:

  • pH electrode
  • storage for titrant
  • serial interface

Usage and accessories:
The TITRALAB TIM 845 apparatus can be used in the following areas:

Food & Beverage
· Total acidity: wine, vinegar, fruit juices, milk
· Chloride: milk, butter, other dairy products
· Ascorbic acid: fruit juice and food
· Free & Total SO2: wine and fruit juice
Environment & Water
· pH & Alkalinity
· Total Hardness
· Chloride
· Chemical Oxygen Demand
Chemical & Plating
· Acid-base determinations in aqueous/non-aqueous media
· Imposed & zero current redox determinations
· Complexometric determinations
· Silver & precipitation determinations
Petrochemical
· TAN/TBN: according to ASTM D664, D1159, D2896, ISO 3771
· Bromine Index and Bromine Number: according to ASTM D1491, D7210
· Hydrogen sulphide and Mercaptans: according to ASTM D3227

The apparatus has all the elements required for a fully functional workstation:
- a titration manager integrating all functions of a modern potentiometric titrator
- one or two high-resolution burettes with a wide choice of volumes
- one electrode input for standard pH or mV potentiometric titration, one for imposed current
  titration
- a titration stand with a magnetic stirrer accommodating beakers from 5 to 400 ml and offering
  optional propeller stirring
- a full set of cables for easily completing your workstation installation.

Properties of analyzed samples
Liquid samples. The apparatus doesn’t use solid or gaseous samples.

Results
Precision titrations that can be used in several processes.

A short description of the technique
TITRALAB TIM 845 is an apparatus used for automatic titration, it can be linked to a computer for data storage, it can use both predefined methods as well as newly created ones. The detachable stand can be changed quickly and safely. Because it is easy to adjust and has a high resolution burette this device ensures rapid analyses, with high accuracy. The accurate display of the titration curve in real time and that of the main parameters, allows the easy pursue of the titration process. The final dispatch of the analysis allows the user to access an ample data base with results shown in graphical mode.

Services offered
With TITRALAB TIM 845 you can benefit from high quality results at the touch of a button. It is ideal for routine applications. It is easier to use than ever before. TITRALAB TIM 845 represents the best value for money on the market for routine potentiometric titrations, regardless of its application area.

Contact:
Person responsible for device:

 

Contact: TOP

Head of Laboratory:
Phone: 0721072589, 0757017124
Dr. A. Paunescu-Podean str., no. 144