Simple Spectrophotometric and Titrimetric Methods for the Determination of Sulfur Dioxide

Abstract

The proposed work describes a simple spectrophotmetric as well as a titrimetric method to determine sulfur dioxide. The spectrophotometric method is based on a redox reaction between sulfur dioxide and iodine monochloride obtained from iodine with chloramine-T in acetic acid. The reagent iodine monochloride oxidizes sulfur dioxide to sulfate, thereby reducing itself to iodine. Thus liberated iodine will also oxidize sulfur dioxide and reduce itself to iodide. The obtained iodide is expected to combine with iodine to form a brown-colored homoatomictriiodide anion (460 nm), which forms an ion-pair with the sulfonamide cation, providing exceptional color stability to the system under an acidic condition, and is quantitatively relatd to sulfur dioxide. The system obeys Beer's law in the range 5 - 100 microg of sulfur dioxide in a final volume of 10 ml. The molar absorptivity is 5.03 x 10(3) l mol(-1)cm(-1), with a relative standard deviation of 3.2% for 50 microg of sulfur dioxide (n = 10). In the titrimetric method, the reagent iodine monochloride was reduced with potassium iodide (10%) to iodine, which oxidized sulfur dioxide to sulfate, and excess iodine was determined with a thiosulfate solution. The volume difference of thiosulfate with the reagent and with the sulfur dioxide determined the sulfur dioxide. Reproducible and accurate results were obtained in the range of 0.1 - 1.5 mg of sulfur dioxide with a relative standard deviation of 1.2% for 0.8 mg of sulfur dioxide (n = 10).

Manipulating the Surface Chemistry of Quantum Dots for Sensitive Ratiometric Fluorescence Detection of Sulfur Dioxide

“…Currently, several conventional techniques have been employed for the monitoring of the SO 2 level, such as titrimetry, spectrophotometry, polarographic methods, physical or chemical adsorption, electrochemical sensors, flow injection, chemiluminescence, and ion chromatography methods . However, there are intrinsic limitations for these methods because they are often expensive, time-consuming, or require complicated instrumentation.…”

The Persian lime peel extract‐loaded tragacanth gel coating for sodium metabisulfite reduction in Pacific white shrimp ( Litopenaeus vannamei )

“…The thiobarbituric acid reactive substances (TBARS) was measured at 532 nm using a UV‐160 spectrophotometer (Jenway, UK) and expressed as milligram malondialdehyde (MDA)/kilogram (Basiri et al., 2015). The total SO 2 residue in shrimp was conducted by iodometric titration method (Yogendra Kumar et al., 2006).…”