Dry cleaning processes

The precautions for the use of perchloroethylene conespond with those for trichloroethylene (Table 5.52). The dry cleaning process, and its safety measures comprise ... 

Figure 9.11-1 Schematic representation of the dry-cleaning process, displaying different steps from A to D.

Liquid CO2 has a lower density than the liquid organic solvents normally used in conventional dry-cleaning processes, as shown in Table 9.11-1. Moreover, its viscosity is one order of magnitude lower than organic solvents. As a consequence, the jet-cleaning agitation seems to offer the more feasible approach for C02 dry-cleaning machines. 

Physical properties of solvents commonly used in dry-cleaning processes... 

The development of surfactants for C02 has made possible the commercialization of a dry cleaning process replacing perchloroethylene (R. Carbonell) ... 

When non-aqueous surfactant solutions are used to remove soils from fabrics, furs, leathers (so-called dry-cleaning process), solubilisation is a quite necessary and sufficient condition for the soil removal considering sufficiently low CMC values. The same also applies to washing of metal surfaces where surfactant additives are often added both to polar (alcohols, ketones, etc.) and non-polar media (aliphatic or aromatic hydrocarbons and their mixtures). 

Carbon dioxide has also been successfully introduced into some dry-cleaning processes and various consumer formulations now no longer contain a VOC solvent. 

Laundry tag papers Fastness to dry cleaning process Specific pigment pastes... 

A competing CO2 dry cleaning process was marketed by Global Technologies. Instead of a conventional basket unit, the system, called DryWash, uses jets of liquid CO2 to agitate clothing [40]. 

Alkyl halides are primarily used as industrial solvents. Carbon tetrachloride, CCI4, was once used extensively in the dry-cleaning process, but it has been replaced because of its toxicity and carcinogenic effects. (See the Chemistry in Action on p. 506.)... 

The dry-cleaning process is indicated by a circle, and the letters within the circle provide information on the solvents to be used during the dry-cleaning process, which is needed by professional textile cleaners. The letters A, P or F inside the circle indicate any solvent, any solvent except trichloroethylene and petroleum solvent, respectively. The line below the circle indicates limitations in the dry-cleaning process, which may be related to mechanical action, addition of moisture and/or drying temperature. A cross on the circle indicates do not dry-clean . 

Further applications as a preservative in industrial functional fluids, as a sanitizing agent in dry cleaning processes and in oil based mop saturants. 

The compound does not exhibit either special activity or cost effectiveness. It proved well in trials when used as a sanitizing agent in the dry cleaning process because of its good solubility in chlorinated hydrocarbons. 

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