The pH analysis is present in several sectors, such as sanitation, food and beverage industries, as well as the chemical and pharmaceutical industries, among many others, due to its importance in processes and the environment.
The pH plays a crucial role in the health of bodies of water, such as rivers and lakes. Furthermore, it ensures product quality, the efficiency of chemical reactions, the safety of production processes, and the longevity of equipment.
Theory and methodologies for pH analysis
pH is defined as the hydrogen potential of a solution and it can be characterized as acidic, neutral, or basic. pH is related to the concentration of H+ ions in the solution and is determined through the correlation: pH = -log [H+].
This parameter is analyzed using two methodologies:
Colorimetric
The colorimetric method essentially involves changing the color of a substance after it comes into contact with an alkaline or acidic medium. Initially, a series of buffered solutions were prepared with characteristic colors, forming a colorimetric scale that would be compared with the sample. This method was quite imprecise.
With the evolution of industry and its production processes, various industrial segments began to require more precise techniques to ensure the quality of their products. In this context, electrochemical techniques gained more significance.
Potentiometry
Potentiometry is a methodology used to correlate electrical potential with the concentration of H+ ions in solution.
The potentiometric method is the most common and provides the most reliable results, using measurement and reference sensors.
pH application possibilities
pH has a strong presence in industry, such as in boilers (steam generation), acting to prevent corrosion in pipes and the boiler body.
In Water Treatment Plants and Sewage Treatment Plants, the pH is present in the prevention of corrosion and incrustation of distribution networks, in the efficiency of sanitization, in compliance with each country's sanitary and environmental laws.
Furthermore, the pH must be adjusted before disposal, complying with the respective legislation of each country.
In sugar and alcohol plants, pH is present in fermentation vats, boilers, and juice clarification. In the food industry, pH influences the stability of preservatives and the treatment of water and effluents.
For these applications, Digimed has a range of instruments, such as analyzers, transmitters, controllers, as well as laboratory and field meters, and electrodes for special applications:
TH-4004
pH analyzer, transmitter, and controller;
Reading range: -2 to 20 pH;
Automatic temperature compensation;
Analog output: two 4 to 20 mA;
Discrete output: two NO1A/250V ac;
Digital RS485 output;
IP67 protection rating;
24Vdc/90 to 240 Vac power supply
TS-71X
Retractable insertion probe
Body material: PP, Kynar, or stainless steel
TS-21X
Transfluency probe
Body material: PP, Kynar, or stainless steel
P-05
Submersion Probe
Body material: PP or 316 stainless steel
DME-CMA1
Antimony electrode
For media containing HF
PTFE junction
Ag/AgCl reference
DME-CVR13
Combined glass electrode
For aggressive and/or fouling media
PTFE junction
Ag/AgCl reference
DM-220
Laboratory pH Meter
pH Range: -2 to 20°C
Data Transmission: USB-C or Bluetooth
Memory: Up to 3,000 Records
DM-200P
Portable pH, ORP, and Temperature Meter
pH Range: -2 to 20°C
Digital Output: USB-C
Memory: Up to 3,000 Records
To learn more about our instruments and solutions, contact our team of experts.