Method and device for automatic determination of lime activity by titration

Abstract

The invention relates to a method and a device for automatic determination of lime activity by titration, and the device comprises a titration rack, a burette, a flowmeter, a titration cup, a stirrer, a PH electrode, a titration control device, a titration table, and a water-bath heater. The burette is connected with a titrant bottle, and is provided with a titration switch. The titration control device is respectively connected with the PH electrode, the flowmeter and the titration switch circuit. The determination comprises the following steps: (1) accurately weighing 50.0 g of samples with a particle size of 1-5 mm, adding 4 mol / L hydrochloric acid into the titrant bottle; (2) setting the titration control device; (3) measuring 2000 ml water into the titration cup, stirring and heating to 40 DEG C; (4) adding the sample into the titration cup for digestion, starting the device for automatic titration; (5) displaying the consumption amount of the hydrochloric acid consumed by the titration. According to the invention, the PH value is used for titration control; the digestion reaction and the neutralization reaction are completed synchronously; precision of the hydrochloric acid amount is realized; the accuracy for lime activity determination is improved; and multifunctional analysis of the test data is realized through the titration control device.

Description

technical field [0001] The invention belongs to the technical field of performance testing of chemical materials, and relates to a method and a device for testing lime activity, in particular to a method and a device for automatically measuring lime activity by a titration method. Background technique [0002] The water activity of lime is an important index to test the quality of lime. Lime reacts with water to form calcium hydroxide, commonly known as slaked lime, and this reaction is also known as the digestion reaction of lime and water. The digestion reaction of lime with water is the main method to characterize the activity of lime. [0003] There are currently two methods for testing lime activity in the world, hydrochloric acid titration and temperature rise method. Domestically, hydrochloric acid titration is used for measurement, and the current testing standard is YB / T105-2005 "Metallurgical Lime Physical Properties Test Method". The basic test principle and re...

AI Technical Summary

Problems solved by technology

[0004] The prior art measures the activity of lime completely by manual operation, and its shortcomings include: 1. There are many human factors in the detection process, large errors, and low accuracy of activity test results

2. The equivalence point of titration is judged by the color change of phenolphthalein indicator. Phenolphthalein is a weak organic acid. The discoloration range of phenolphthalein is 8.2-10.0, that is, the color pH value of phenolphthalein reagent is 8.2, so the pH value after the digestion reaction is The color reaction will only appear at 8.2, and there is a hysteresis at the equivalence point

3. It is not very obvious when the color changes. Due to the effect of vision, there is a large error in the control of the equivalence point

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