formazinstandardlösningar

Formazin standardlösningar, often referred to as formazin turbidity standards, are widely used in analytical chemistry and environmental monitoring for calibrating nephelometers and turbidimeters. These instruments measure the turbidity or cloudiness of liquids. Formazin is a stable, insoluble polymer that is typically prepared in a specific concentration to serve as a reference material.

The preparation of formazin standards involves reacting hydrazine sulfate with hexamethylenetetramine (HMTA) under controlled conditions. This reaction produces a suspension of spherical, non-porous particles of uniform size, which mimics the scattering properties of suspended solids found in real-world samples like water. The concentration of formazin is expressed in Formazin Nephelometric Units (FNU) or Formazin Turbidity Units (FTU), which are equivalent.

These standards are crucial for ensuring the accuracy and reliability of turbidity measurements. Different concentrations of formazin solutions are available, ranging from low turbidity values suitable for drinking water analysis to higher values for wastewater or industrial process streams. Regular calibration with formazin standards is essential for instruments to provide consistent and comparable results across different laboratories and over time. The stability and reproducibility of formazin make it a cornerstone in turbidity metrology.