Envco – Environmental Equipment

The CHEMets MethodTo perform a test, immerse the CHEMet ampoule into the sample and snap off the tip.
(Step 1)- the correct volume of sample is automatically drawn in, filling the ampoule; a small inert gas bubble remains in the ampoule. To facilitate mixing the sample and reagent, tilt the ampoule back and forth so the bubble travels from end to end.
(Step 2). In 2 minutes or less, quantify the result by comparing the filled ampoule to the appropriate color standard(s)
(Step 3). For higher concentrations, the flat comparator is used. For lower concentrations, the round comparator is used. The ampoule is compared with the standards until a color match is found.

Kits include 30 ampoules, comparator(s), accessory solution(s)(when necessary), a sample cup, and instructions. Refill packs of 30 ampoules and accessory solutions are available separately. Comparators have a 2-year shelflife. Material Safety Data Sheets are provided in test kits.

CHEMets ampoules are designed for maximum simplicity and accuracy. Each glass ampoule is 7 mm in diameter, 100 mm in length, with a tapered, pre-scored tip; reagents are vacuum-sealed inside.

CHEMetrics' cyanide test kits are applicable to the monitoring of effluents and surface water supplies. It is recommended, however, that the sample be distilled and hydrogen sulfide be removed prior to analysis.

Methods
TheIsonicotinic-Barbituric Acid Method
Reference: S. Nagashima, Spectrophotometric Determination of Cyanide with Isonicotinic Acid and Barbituric Acid, International Journal of Environ. Anal.

Chem., 1981, Vol. 10, pp. 99-106. With CHEMetrics' method based on the isonicotinic/barbituric acid procedure, chlorine is added to a sample that has been buffered to pH 6. The resulting cyanogen chloride reacts with isonicotinic and barbituric acids to form a blue color. Results are expressed as ppm (mg/L) CN.

This chemistry provides two advantages over the more commonly used pyridine methods: (1) Theshelflife of the reagent is extended, and (2) the analyst is not exposed to noxious and hazardous fumes from the pyridine reagent.

The Silver Nitrate Method
Reference: APHA Standard Methods, 20th ed., pp. 4-38, Method 4500-CN- D (1998).
CHEMetrics employs silver nitrate as the titrant and 5-(p-dimethylaminobenzylindene) rhodanine as the indicator. A color change from orange to yellow signals the end of the titration. Results are expressed as ppm (mg/L) CN.

Ordering Information
Range: 0-0.1 & 0.1-1 ppm
K-3810 Range: 0-0.1 & 0.1-1 ppm MDL: 0.005 ppm / Method: Isonicotinic-Barbituric Acid
R-3810 CHEMets Refill, 30 ampoules
A-38001 Neutralizer Solution Pack, six 20 mL bottles, Shelf-life 2 years
A-38011 Activator Solution Pack, six 10 mL bottles, Shelf-life 2 years
C-3801 Low Range Comparator, Shelf-life 2 years: 0, 0.01, 0.02, 0.03, 0.04, 0.06, 0.08, 0.10 ppm
C-3810 High Range Comparator, Shelf-life 2 years: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 1.0 ppm
Kit comes in a plastic case and contains everything needed to perform 30 tests: Refill, Low and High Range Comparators, Neutralizer Solution, Activator Solution, 5 mL sample cup & top, instructions, and MSDS.

Range: 5-50 ppm
K-3815 Titrets Kit Range: 5-50 ppm MDL: 5.0 ppm / Method: Silver Nitrate
Increments: 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 9.0, 10.0, 12.5, 15.0, 17.5, 20.0, 25.0, 35.0, 50.0 ppm
Kit comes in a cardboard box and contains everything needed to perform 30 tests: thirty ampoules with valve assemblies, Indicator Solution, titrettor, 25 mL sample cup, instructions, and MSDS.