Superheated solution

The very troublesome bumping is avoided by adding porous pot, in pieces about half the size of a pea, before the boiling begins. When the pieces of pot become inactive they are replaced by new ones (do not drop them into superheated solutions ). When violent bumping occurs in large volumes of solution the addition of wooden rods is to be recommended. 

Add a small amount (0.1% of the solute weight is sufficient) of pelletized Norit to the colored solution and then boil the solution for a few minutes. Be careful not to add the charcoal pieces to a superheated solution the charcoal functions like hundreds of boiling chips and will cause the solution to boil over. Remove the Norit by filtration as described in Step 4. 

THERMAL GROWTH OF BUBBLES IN SUPERHEATED SOLUTIONS OF POLYMERS... 

Numerical simulations of vapor bubble growth in a superheated solution of polymer were performed,using iterative algorithm to account for the diffusion coefficient dependence on concentration in the interval (k, ko). The results are reproduced in Figures 7.2.10-7.2.12,... 

Thus, the rate of expansion of vapor bubbles in superheated solution of polymer is lower than in pure solvent due to diffusion resistance. But in diluted solution at rather small superheats the mechanism of diffusional retardation can be suppressed due to a weak dependence of Ts on kfl in this concentration range. Another important conclusion is that in concentrated solutions it is practically impossible to attain values Ja 1 by increasing the superheat because of low values of the corresponding Sn numbers. 

Cross-sectional areas substantially facilitate the disengagement of gases and vapours. This is particularly important for flash evaporation of the superheated solutions or for foaming products. 

---