Propan-1,2-diol

Propane-1,2-diol (propyleneglycol) [57-55-6] M Dried with Na2S04, decanted and distd under reduced pressure. 

The reaction was also extended to propane-1,2-diol, butane-2,3-diol, and butane-1,3-diols (74ZOR953). 

As early as 1904, 1,2-Propanediol Dinitrate was proposed (Ref 3) as an additive to lower the freezing temp of NG, but its practical application on a large scale was hindered by lack of the raw material, propane-1,2-diol. It is only recently that the synthesis of glycol from ethylene led to the development of a method for producing methyl glycol from propylene via cnioro-hydrin. Even so, propylene-1,2-glycol is somewhat more expensive than glycols derived from ethylene (Ref 9)... 

Propane-1,2-diol, 3-mercapto-metal complexes, 2,804 Propan-l-ol, 2-amino-2-methyl-copper(II) complexes, 2,795 Propan-l-ol, 2,3-dimercapto-chelating agent heavy metal poisoning, 6,767 Propan-l-ol, 3-(methylamino)-copper(II) complexes, 2,795 Propan-2-ol... 

The hydrocarbon groups contribution values from chosen experimental AIT are subtracted. Thus propane-1,2-diol has one CHgOH, one CHOH and one CH the chosen ATT value is 371 °C (see Part Three). 

A metal polishing fluid of a similar composition that contained propane-1,2-diol, nitric acid, hydrogen fluoride and silver nitrate detonated thirty minutes after being used. 

Fell and Bari (89) also studied the rhodium-catalyzed reaction. A rho-dium-N-methylpyrrolidine-water catalyst system was very effective for producing the propane-1,2-diol acetate directly. The best yields (>90%) of product of about 9 1 alcohol aldehyde ratio were obtained in the region of 95°-l 10°C. This range was very critical, as were other reaction parameters. Rhodium alone gave the best yield of aldehyde (83%) at 60°C. Triphenylphosphine as cocatalyst induced the decomposition of the aldehyde product. 

E 475 Polyglycerol esters of fatty acids E 476 Polyglycerol polyricinoleate E 477 Propane-1,2-diol esters of fatty acids E 479b Thermally oxidised soya bean oil interacted with mono- and diglycerides of fatty acids E 481 Sodium stearoyl-2-lactylate... 

Emulsifier 477 Propan- 1.2-diol esters of fatty acids 25 7th Series 539, p 24, 1973... 

Fig. 11.5 Price evolution for glycerol and propane-1,2-diol. (After [98]).

In contrast to Raney Ni, no hydrocarbons are formed over pure Raney copper, while propane-1,2-diol is produced with a selectivity of 66% at 85% glycerol conversion at 3 MPa and 513 K. It has been verified that the excellent selectivity is due to the high stability of propane-1,2-diol under the reaction conditions. 1,3-Propanediol is not stable and converts almost quantitatively into 1-propanol... 

In another patent, very high propane-1,2-diol yields were obtained with a multi-component oxide catalyst consisting of the metals Co, Cu, Mn and Mo, and P. At 523 K under 25 MPa, glycerol is almost quantitatively converted into propane-1,2-diol. In contrast to most studies, the reactions were performed with pure (99.5%) glycerol instead of aqueous dilutions [123],... 

Time-resolved fluorescence experiments carried out with 1,2-benzanthracene quenched by CBr4 in propane-1,2-diol show a better fit with the Collins-Kimball equation than with the Smoluchowski equation. 

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