Sulfate is widely present within natural waters in different concentrations. Sulfate concentration is to be kept within a strict range for drinking water, especially since this value can be high near mine drainage points. Sulfate is also rigorously tested in the production of beverages such as beer, due to its significant effect upon odor and taste.
Hanna Instruments offers a wide variety of instrumentation for measuring sulfate. Products include a titration system that can use a solid-state lead/sulfate Ion-Selective Electrode (ISE). The ISE is used as an indicator following the progress of a titration with lead perchlorate for sulfate.
In addition to titration system for measuring sulfate, Hanna offers a photometric method and chemical test kits that use reagents. The reagents contain barium chloride crystals that precipitate sulfate. For the photometric method a portable or benchtop photometer is then used to determine the sulfate concentration in a sample.
Below are the most common products used for measuring sulfate.
Titration systems with precision dosing pumps are available to use with a lead/sulfate ISE for performing a titration for sulfate. Options for titrators include version with two analog inputs and two dosing pumps.
Lead electrodes are potentiometric devices used for the titration of sulfate with lead perchlorate. A Lead electrode may be used as an indicator to follow the progress and detect the endpoint of a precipitation titration of sulfate (with concentration >50 ppm) using lead perchlorate standard. During the titration the sensor follows the lead concentration while small additions of lead perchlorate titrant are added. The lead reacts with the sulfate ions forming a precipitate. At the stoichiometric end point, a change in mV occurs.
Solutions for sulfate determination include sulfate standards and ISA used for measurement. Solutions also include the CAL Check standards for verifying and, if needed, the calibration of our portable photometers. Each CAL Check standard is supplied with a Certificate of Analysis stating the accuracy and traceability of the standard
Spectrophotometers are available that have the sulfate method pre-programmed into the meter. The spectrophotometer offers the highest precision due to the quality of the optical system that has a wavelength accuracy of +/- 1.5 nm. The spectrophotometer allows for custom methods to be used as well.
Benchtop photometers include multiparameter versions for water and wastewater treatment and one for nutrient analysis. These photometers can measure sulfate in multiple ranges. All benchtop have a digital pH electrode input allowing it to be used as a traditional pH meter.
Portable photometers are available to measure sulfate. The portable photometer has the CAL Check feature that allows for performance verification, and if needed, recalibration using the CAL Check standards. The meter is available as a meter only option or as a kit. The kit version includes a rugged carrying case and CAL Check standards.
Chemical Test Kits
A Chemical Test Kit (CTK) is available to measure sulfate. There are two different methods to choose from. One is a turbidimetric method that has two ranges and can measure up to 100 mg/L (ppm). The other is a high range titration method that can measure up to10,000 mg/L. Both CTKs are supplied complete with all necessary items to perform the measurement.
Replacement reagents for the photometers and chemical test kits.
Accessories include the replacement cuvettes and caps for the photometers.