Toxic Cloud In Spain Caused By Rocket Fuel

A toxic orange cloud hanging over Igualada was caused when two chemicals being delivered to the Simar S.A. storage facility were accidentally mixed.

The chemicals being delivered were nitric acid and ferric chloride.  These are the sole ingredients of the WW2 S-Stoff hypergolic rocket fuel.  Two civilians and three firefighters suffered minor injuries, The Guardian reports.  The orange cloud which was created by the explosion stayed in the air a long time.

Screen grab from The Guardian.

S-Stoff, a WW2 German rocket fuel, is made by mixing nitric acid with ferric chloride.  It was the fuel used in the experimental Ruhrstahl X-4.  It is also known as red fuming nitric acid.

S-Stoff is hypergolic, meaning that the mere act of mixing the two chemicals causes spontaneous  ignition.  No igniter is needed.

This incident resembles the explosion and fire in the Philips factory in Eindhoven, about the late 1960s - early 1970s.  That explosion and fire was caused when two chemicals used in the manufacture of CRTs were accidentally mixed during a delivery.  Following that accident, Mullard  arranged that the two chemicals, one of which was MEKP, would be delivered on different days and at different gates to its U.K. CRT factory.

Plus ça change ...

I wonder if the lesson of history will be learned this time. 

If two chemicals will explode or combust when mixed they must:

be delivered by different trucks

on different days

to different storage facilities.

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