Sulfide Test Kit(DPD Method)

1. Specification

Name: ozone (with residual chlorine) in water test kit

model: LH2008

Type: semi-quantitative

Color reaction: none-blue

Testing range: 0.02-0.05-0.1-0.2-0.4-0.5-0.6-0.8mg/L

Packing: 30units/box

Application areas: this test kit can be used in analysis of sulfide in water.

Shelf life: at least 1year

2. Features of product 

Quick and easy

Operating in accordance with the instructions, users can complete the sulfide test independently without specialized training. Five minutes is enough to complete the analysis of one water sample.

Accurate and reliable

This method equals to N, N-diethyl-p-phenylenediamine (DPD) method (GB/T5750.6 -2006). In the presence of high-iron ions, sulfides react with N, N-diethyl-p-phenylenediamine to form a blue complex.

The range of the determination: 0.02~0.8mg/L. If the concentration is out of the range, please repeat the operation after appropriate dilution of the water sample.

3. Operation

1. Fill the tube with 15mL testing liquid.

2. Add one pack of reagent I, the add 0.5mL reagent II, wait for 5 minutes.

3. Looking from up to the bottom of the tube, compare the shown color with colorimetric chart, come out a result.

Note: SO₃^2-, S₂O₃^2-, NO₃^-, SCN^-, I^-, Pd²⁺, Hg2⁺, Cu²⁺ will affect the result.

4. Background of development

Sources of sulfide

Ground water (especially hot spring water) and domestic sewage usually contain sulfides, some of which are produced by decomposition of sulfur-containing organic compounds or sulfate reducing due to the role of bacteria under anaerobic condition. Industrial wastewater coming from industrial and mining enterprises, such as coking, gas, ore dressing, dyeing, tanning and etc., also contain sulfides.
Sulfides in water mainly include H₂S, HS^- and S^2-. Sulfides existing in suspensions are soluble sulfides, acid-soluble metal sulfides and the non-ionized organic, inorganic sulfides.

Significance of sulfide test

Hydrogen sulfide can easily dissipate from the water into the air, producing the stink smell and with high toxicity. It can react with the disulfide bonds of oxidase, cytochrome in human body and other such substances, affecting the oxidation process of cellular, resulting in tissue hypoxia and endangering human life. In addition to its own capability of corrosion of metals, hydrogen sulfide can also be oxidized into sulfuric acid by the biology in sewage, thus eroding the sewer. Therefore, the sulfide is an important indicator of water pollution (clean water, olfactory threshold for hydrogen sulfide is 0.035μg / L).