Glycols reclaiming

This reaction is truly tempting because it potentially satisfies the need in the search for a way to reclaim the chemical value of a polyurethane recycle foam project [12, 13]. When a polyurethane foam is hydrolyzed, it gives aromatic diamine and polyether polyol, both in very crude forms. The diamine can be purified by regular means, but the crude polyether polyol cannot be easily cleaned up due to its polymeric nature. If this Ganem reaction can work well, the polyether polyol stream can be converted to a low-molecular-weight chemical, which can then be purified by conventional process such as distillation. Indeed, when this reaction was tried on a polyether triol of 3000 molecular weight as a model, the diacetate of propylene glycol was isolated by distillation. Unfortunately, the yield was too low to be of practical interest. 

The polyols which function as modifiers include ethylene glycols, 1,4-butanediol, polyether polyols and polyester polyols. In recent years aromatic polyesters prepared from reclaimed PET (polytetraethylene terephthalate) or the distillation residue of DMT (dimethylterephthalate) have appeared as modifiers for urethane-modified isocyanurate foams (73, 78). These aromatic polyesters are produced by the transesterification of reclaimed PET or DMT distillation residue. 

Hydrogenated tallow amide Isopropanolamlne Polyethylene glycol PPG-20 Tris [1-(2-methyl-azlrldlnyl) phosphine oxide] rubber processing chemical synthesis 6-t-Butyl-m-cresol rubber processing, synthetic 1-Decanethiol 1-Hexadecanethiol 1-Hexanethiol 1-Octadecanethiol 1-Tetradecanethiol rubber reclaiming... 

The cardinal rule for proper disposal of any organic solvent also applies to the glycols. Do not dump any solvent into any sewers, on the ground, or into any body of water. Any unused or uncontaminated solvent can be sent to a licensed reclaimer or to an approved incinerator. Any contaminated solvent may have to be analyzed by a method recommended by the solvent manufacturer prior to recycling in a licensed facility. The solvent producer should be able to answer any questions on recycling or disposal practices. Any disposal process must follow all local, state, and federal regulations... 

Simmons, C. V., 1991, Reclaiming Used Amine and Glycol SoVaAcfai, Laurance Reid Gas Conditioning Conference Proceedings, Univ. of Oklahoma, Norman, OK. 

The design and operation of a trailer-mounted vacuum reclaimer which was used to process the TEG of a number of dehydration units by the La Vaca Gathering Company, is described by Armstrong (1979). The unit was designed to process 0.5 gpm of glycol, but actually handled up to 2.0 gpm. The reclaimer operates in a semi-batch mode, i.e., feed is continuous at 0.5-2.0 gpm until sufficient non-volalile material accumulates in the heater vessel to raise the boiling point to 400 F at 28 in. of mercury vacuum. The reclaimer is then shut down and cleaned out. 

Most commercially used solvents are very stable and reclaiming is not required. However, water removal by distillation is sometimes necessary to maintain the water concentration of the solvent at low levels. Alternatively, the feed gas can be dehydrated by glycol injection or other means to keep water out of the system. 

Filters of this type can be incorporated in recycling and coolant reclamation systems ranging from 220 litres to 13,500 litres capacity. The types of fluids that may be reclaimed include water-based coolants, synthetic hydraulic fluids, water/glycol... 

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