Abstract: The present invention provides a method of determining chemical oxygen demand (COD) for a sample with a high concentration of chloride. The method includes obtaining the sample, determining a concentration of chloride in the sample to obtain a known concentration of chloride in the sample, dosing an amount of the sample, an acid and an oxidizing agent into a container to obtain an analyte, heating the container containing the analyte, photometrically determining a preliminary chemical oxygen demand (COD) of the analyte in an analytic device, and correcting for the high concentration of chloride using a chloride correction to obtain the chemical oxygen demand (COD).

Abstract: A liquid analysis system for a photometric determination of an analyte in a liquid sample includes an analyzer comprising a photometer, an RFID parameter reading device and an identifier reading device, and a cuvette package comprising an RFID parameter transponder and a plurality of test cuvettes of one batch. Each test cuvette comprises a reagent. Batch identification and batch-specific reagent data are stored in the RFID parameter transponder. Each test cuvette comprises a batch-specific identifier including a batch identification. The batch identification is configured to be read by the identifier reading device.

Abstract: A liquid analysis system for a photometric determination of an analyte in a liquid sample includes an analyzer comprising a photometer, an RFID parameter reading device and an identifier reading device, and a cuvette package comprising an RFID parameter transponder and a plurality of test cuvettes of one batch. Each test cuvette comprises a reagent. Batch identification and batch-specific reagent data are stored in the RFID parameter transponder. Each test cuvette comprises a batch-specific identifier including a batch identification. The batch identification is configured to be read by the identifier reading device.