Contrabasso
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V2O5 catalyst
Does anyone have a vanadium pentoxide catalyst bed method that they wish to share.
I have some V2O5 and was considering a plug of asbestos fibre (yes I know it has hazards) covered with v2o5 in a stainless (316 ??) tube initially
heated to red in a blowtorch flame and see whether it sustains the exothermic reaction.
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smuv
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Not sure what reaction you are talking about, so I cannot comment too much further, but...
I have used ordinary fiberglass insulation as a solid support for alumina catalyzed vapor phase dehydration of alcohols/cracking of naptha. It worked
pretty well. Burn off the dyes and stuff, but watch out, it is easy to melt fiberglass with a torch. Make sure the catalyst is finely divided and
just sprinkle it on the insulation (I suppose you could put the two in a plastic container and shake), then load the insulation into the tube. Make
sure you don't pack the insulation too tightly, as this will increase the pressure drop across the catalyst (ie. decrease flow rate).
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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Contrabasso
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Target is a sulphur candle producing SO2 in air, Hot V2O5 catalysing the conversion to SO3. SO3 dissolved in sulphuric acid and the resultant oleum
diluted if and as necessary. Gas flow created by a fridge pump protected by filters and limestone chips. Product made in a "dreschel bottle" of
several litres capacity -probably a hdpe water carrier with a tap for delivering the product acid. Catalysis tube stainless steel, warm tubes glass
cold tubes flexible pvc.
If I need a new pump every gallon of oleum that will be a cheap price to pay
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not_important
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Try searching the site - there's been a number of discussions on this. Temperature control is important, see the graph below.
The actual catalyst is a fluid formed from V2O5, alkali sulfates, and further SOx. Thus commercial catalysts are dopd with K, Rb, and/or Cs salts.
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hissingnoise
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A moisture trap with CaCl, NaOH or better H2SO4 will help prolong the life of the "pump". . .
When I saw fridge-pump mentioned I thought you were going to use it as a blower but you seem to know that the exhaust contains atomised oil as a mist.
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Contrabasso
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One idea was to create the flow by very minor depression, so that any leaks would be inwards preventing the escape of SO3.
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