I want to work on hydrotreating processes by waste materials as a catalyst. Can anybody help me?
I worked on a hydrotreatment rig about 30 years ago for a PhD I walked away from after 6 years. I used nickel sulphide as catalyst but fellow students found that many near by transition metals also worked well. It was with a trickle bed reactor at between 300 to 350 C and about 150 bar (cyclinder ressure) of Hydrogen. The flow rate was about one reactor volumn per hour of fluid that was hdrogenated, desulphurised de-oxygenated and demetalated.
What are you trying to do with your waste?
The Fe is a good metal for the pre-treatment of residues, it is cheap, you can use first this catalyst to pre-clean the residue and then you can use a second catalyst in a second reactor based in other catalyst like Ni, Co, etc.
The problem using a expensive catalyst is how to remove this expensive catalyst from the product or sub-products is you are using heavy residues. I recommend you (if you are using problemating residues) use directly Fe catalyst (cheap) and see what is happening in your reaction, then you will have some gases, some more clear residue (to use with other catalysts or processes).
Don´t be afraid of try different possible cheap combinations with Fe (from minerals as support, etc.) with high hydrogen pressure, try it and see the results.
Dear Mr. whyte & Herrador
thanks for your attention. Ni and Pt are more expensive than iron based catalyst.
my catalyst is mixture of Fe2O3, SiO2,CaO and MgO that this is very cheap and available.I want to use it for refining of waste oil engine. indeed we want to prepare valuable product from waste material.
jose thanks for your suggestion this is so good I will do it,
at first i will use fe for HDS, HDN, HDO and for converting of aromatic compound to aliphatic will use Co or Mo.
do you have any suggestion about it?/
thanks again
best regards
I'd be inclined to try the set up that I used which was a trickle bed reactor with your catalyst material in a form that is pellet like so that flow is not restricked. For initial set up I'd try 320 C and a flow rate of about 1 reactor bed (in a trickle bed reactor, downward flow) per hour and in the initial feedstock I'd put an organic sulphur compound in your oil feed for the first few hours as sulphur souce so I knew that the oxide of Fe would be reduced to a sulphide. I'd use as high a hydrogen pressure as your rig can privide up to close to cyclinder pressure 150 - 200 bar. Then I'd put model compounds into the feed to check reactions by GC or what ever analytical methods you have avaiable. I used a clean lubricating oil as a base with models added but after a short period to prove your process works I'd switch to your dirty crude and analyse for what you want to get ride of.
I just used swagelok fittings and stainless tubes to build the rig. I expect that you will need to scale up at some point but to prove the concept I'd just use the common grade 1/4 inch or what ever metric size that is for the small pipes and about 1/2 inch id pipe for the reactor.
I used a needle valve after the back pressure regulator to regulate gas flow and the input pump to regulate oil flow. I used a high pressure seperator that I could isolate and empty to sample and then repressurise before putting back on line.
I used dibenzothiophene made from biphenyl with aluminium chloride and suplhur dichloride as my sulphur souce as it's easy to make and does not smell and has low toxicity. It's also commonly found in petroleum feeds. Both biphenyl and dibenzothiophene were in a clear area of my feed's CG trace.
If you want any more details just ask.
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