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Removal of hexavalent chromium on a fixed bed reactor

I want to know more information about the removal of hexavalent chromium on a fixed bed reactor by reduction with scrap iron.

Mohamed A.
student - Alex, Elraml, Egypt
2003

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Please put your question into context. Mr. Atia--what motivates the question, what information you already know but find insufficient, what grade level you are at, etc. We don't know if you are a post-grad student looking for graphs of reaction rate vs. temperature, concentration and pH for a doctural thesis, or if you're a young student just wondering "what's a fixed bed reactor, dude?" so you can finish your homework. Thanks.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

I want to know more sufficient information about reduction of hexavalent chromium by scrap iron on a fixed bed reactor and I am a post-grad student looking for graphs of reaction rate vs. temperature, concentration and pH for a doctural thesis. and very thanks for your excellent work.

Mohamed A.
student - Alex, Elraml, Egypt
2003

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Thanks. And good question. Iron can be employed 3 different ways towards reduction of chromium. The first is by using ferrous sulphate ferrous sulphate [affil links] as a reducing agent. The second is to apply electricity to iron electrodes, in which case the external source of electricity is providing the reducing power. But the third way (per James W. Patterson's Wastewater Treatment Technology ISBN 0250400863 or 0409900028) is for the chromium to react with elemental iron per:

Cr₂O₇^-2 + 3Fe⁰ + 14H⁺ = 2Cr⁺³ + 3Fe⁺² + 7 H₂O

This requires acidic conditions, i.e., low pH. Paterson references a couple of studies, but without having them in hand, I don't think they offer the depth you are looking for; although surely there is good information to be gotten from them.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

adv.