Polymer waste reclamation by pyrolysis in molten salts

Abstract

The rubber-rich organic fraction from an automobile shredder has been pyrolyzed in a variety of molten salts at temperatures between 380 and 570 °C. The reactions are very rapid. As the temperature Is Increased, the amount of methane Increases, while the C* gases decrease. Gas production was higher [30% (wt/feed)] with more acidic melts such as NaCI/AICI3. Production of lower boiling oils is favored by longer residence times In the reactor. Hydrogen Is the limiting factor In the reactions, the residue being a carbon char. Most efficient conversion of hydrogen in the feed to useful products was obtained using a KCI/UCI melt containing 10% CuCI. Both the nature of the products and the amount of hydrogen retained In the product char depend on the molten salt used as the pyrolysis medium.

Combined molten salt–Ni/Al2O3 as synergistic medium for high-quality syngas production

“…Residual solids, such as char and ash, are retained in molten salt for subsequent handy separation and disposal [2]. The potential benefits of molten salt for solar gasification were first demonstrated by Epstein [5], and subsequently investigated by several research groups [6][7][8][9][10][11][12][13]. Recently, the solar gasification of coal and activated carbon with CO 2 in molten salt has also been investigated [9,11,[14][15][16].…”

Scrap tyre recycling process with molten zinc as direct heat transfer and solids separation fluid: A new reactor concept

“…Molten salt instead of molten zinc may be used to pyrolyse tyres [17] . A major drawback of salt over zinc is that the rCB will be contaminated with salt [18] and, as a result, another unit operation to remove the salt from the rCB would be required. The zinc based process discussed in this paper has, therefore, a significant advantage over the salt based process.…”

A comparative study on thermal and catalytic degradation of polybutylene terephthalate

“…The reason why copper (II) chloride possesses stronger degradation activity than the other catalysts can be explained based on previous research results. Chambers et al [12] have found a few molten salts, like copper (I) chloride, were active in polymer waste reclamation due to their excellent heat transfer properties. In addition, Schmitz et al [13] also reported that copper (II) chloride was active for methanol decomposition between 350 8C and 450 8C.…”