Dipentaerythritol hexanitrate

Pentaerythritol may be nitrated by a batch process at 15.25°C using concentrated nitric acid in a stainless steel vessel equipped with an agitator and cooling coils to keep the reaction temperature at 15—25°C. The PETN is precipitated in a jacketed diluter by adding sufficient water to the solution to reduce the acid concentration to about 30%. The crystals are vacuum filtered and washed with water followed by washes with water containing a small amount of sodium carbonate and then cold water. The water-wet PETN is dissolved in acetone containing a small amount of sodium carbonate at 50°C and reprecipitated with water the yield is about 95%. Impurities include pentaerythritol trinitrate, dipentaerythritol hexanitrate, and tripentaerythritol acetonitrate. Pentaerythritol tetranitrate is shipped wet in water—alcohol in packing similar to that used for primary explosives. 

Dipenta. Code name for Dipentaerythritol Hexanitrate, abbr as DPEHN... 

This stable compd was found to be suitable for prepn of esters and resinous compositions for plastics, or it could be nitrated for conversion into a stable explosive of definite composition, which.is described here under Dipentaerythritol Hexanitrate... 

The mixture of alcohols undergoes nitration with nitric add in the same manner as pentaerythritol, after which the crude product is treated with an equal portion (by weight) of acetone. PETN is insoluble, while nitrodipenta remains in solution with a small quantity of PETN. Water added carefully causes the residual pentaerythritol tetranitrate to predpitate. The solution separates into two layers the upper composed of fairly hydrated acetone containing a small amount of nitrodipenta, and the lower which consists of a saturated solution of nitrodipenta in acetone containing a little water. The bottom layer is removed and treated with an excess of alcohol. Almost pure dipentaerythritol hexanitrate is predpitated. 

The compound is soluble in acetone, but insoluble in water. When technical grade pentaerythritol is nitrated, a certain amount of dipentaerythritol hexanitrate is formed as a by-product. 

Dipentaerythritol hexanitrate DiPEHN is formed as a by product in the synthesis of PETN, and hence can influence its performance. It is dimorphic, the stable modification is Form I (mp 76.0 °C microscope hot stage) (Cady 1974), which can be grown as dendrites from a supercooled melt. Form II starts growing from the supercooled... 

Dipentaerythritol Hexanitrate Anolytical Procedures and Physical Tests. 

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