Preparation method of formaldehyde standard gas

Abstract

The invention discloses a preparation method of standard formaldehyde gas, which comprises the following steps: absorbing 1-10 muL dense formaldehyde solution with 35-40 percent density by microinjector; injecting the dense formaldehyde in the sealing and clean of the first glass injector with full of active carbon column; heating the first glass injector to volatilize the formaldehyde solution; cooling the first glass injector to the indoor temperature; transmitting the formaldehyde gas from the first glass injector to the second and third glass injectors; marking the disposed formaldehyde gas through standard method as the formaldehyde reservation gas; adapting the clean air filtered by active carbon column as diluent to finish the standard formaldehyde gas of random density.

Description

technical field

[0001] The present invention relates to a kind of preparation method of standard gas, more specifically relate to a kind of preparation method of standard formaldehyde gas. Background technique

[0002] The formaldehyde detector uses a relative comparison method for measurement. Usually, the instrument is calibrated with a zero formaldehyde gas and a standard concentration of formaldehyde gas, and the obtained standard curve is stored in the instrument. During the measurement, the instrument compares the electrical signal generated by the concentration of the gas to be measured with the electrical signal of the standard concentration, and calculates the accurate value of the formaldehyde gas concentration. Therefore, zeroing the instrument at any time and frequently calibrating the instrument are necessary tasks to ensure the accuracy of the formaldehyde detector.

[0003] Formaldehyde is chemically unstable, easily soluble in water, and easy to polymerize. ...