TECHNICAL INFO

Storage temperature for formaldehyde The design of tanks and the storage temperature are critical to the stability of aqueous solutions of formaldehyde. Too high storage temperature will accelerate the formation of formic acid. In general, the storage temperature should be maintained as low as possible without precipitation of paraformaldehyde.

Recommended storage temperature rangefor non-stabilized low-methanol formaldehyde

30

40

50

60

70

80

35 40 45 50 55

Weight% of formaldehyde

Sto

rage

tem

pera

ture

[°C

]

Diagram 1. Recommended storage temperatures Formaldehyde

concentration Storage temperature

37 wt% 33 – 37 °C 45 wt% 48 – 55 °C 50 wt% 57 – 64 °C 55 wt% 62 – 72 °C

Table 1. Recommended storage temperatures The temperatures indicated in the chart and table above are applicable for the storage of formaldehyde containing no stabilizer and less than 1 wt% of methanol, when stored in properly designed, insulated and agitated tanks. The optimal storage temperature for an individual case should be verified in full-scale tests, and will depend on the contents of formaldehyde, methanol and formic acid, the storage time, product requirements, as well as the tank conditions (design; agitation; contamination with paraformaldehyde). If the conditions are optimal, it may be

Rev. date 2009-05-04

Please note! This document is for informational purposes only. All material and data found herein are subject to change and should not be relied upon as technical or other advice on any specific matter. Formox accepts no responsibility or liability for the validity of this information.

TECHNICAL INFO

possible to store formaldehyde at a few degrees lower than indicated in the chart and table above. In order to maintain an appropriate safety margin to the flash point, the storage temperature for formaldehyde containing less than 1% methanol should never exceed 72°C. The maximum storage temperature may be further limited by local rules, and/or if the methanol content is higher than 1%. There is a risk for significant formation of formic acid if the storage temperature exceeds 63°C. Typically, 55% formaldehyde can be stored at 62 – 63 °C for up to four days.

Rev. date 2009-05-04

Please note! This document is for informational purposes only. All material and data found herein are subject to change and should not be relied upon as technical or other advice on any specific matter. Formox accepts no responsibility or liability for the validity of this information.