A LOW-PRESSURE GAS BUBBLER EUGENE W. BLANK Research and Development Dept., Colgate-Palmolive-Peet Co., Jersey City, New Jersey
THE USUAL type of gas-absorption bottle is not applicable when dealing with small volumes of gases at very low pressures. A design is presented here for a gas-absorption bubbler that operates efficiently under these conditions. The figure shows the constructional details and dimensions of the new form of bubbler. The dimensions
may be varied widely to meet the requirements of the work. The bubbler is constructed entirely of glass and may be made in two sections, the perforated and spirally wound portion being subsequently attached to the straight inlet tube. The numerous inlets along the under surface of the spiral section are circular, 2 to 3 mrn. in diameter, and placed approximately 1 em. apart. Perforating the glass tube is a simple operation that requires no discussion here. After the bubbler has been assembled according to the drawing it is tightly wound in a flat spiral or helix with a slight angle of inclination. The bubbler is mounted in a wide-mouthed bottle of low form or in a cut-off cylinder. Any of the usual liquid absorbents may be used. A volume of absorbent sufficient to cover the outlet of the bubbler tube is all that is required; this will be 1 to 2 em.in depth. The coiled tube has a diameter of approximately 4 cm. The operation of the bubbler is simple. As gas bubbles form in the tube they tend to rise, due to the inclination of the tube, and in passing along the latter draw fresh portions of solvent through the openings in the bottom of the bubbler tube, effectmg continuous circulation.