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I will also contribute where i can. I have already helped some one requesting info on gum arabic I think. So all should be good I'd also like to thank the maintainers of this sight as they seem pretty sharp on the ball. To date this is the first forum I've seen on the web for chemical engineers, which is nice because most other forums target more computer orientated stuff.

I am a final year chemical engineering student. For our final year design we are to design a polytetrafluoroethylene (PTFE), -CF2- plant. My questions mainly pertain to data gathering at the moment, so I am hoping to develop this thread as i go along with logical flow starting from the beginning and running onto the end. I will try and post our groups final report here if they allow me too, but i can not guarantee it. Either way i shal try and be as open as possible with information that i acquire with that let's begin. My starting point was to obtain as much info as possible to that end i have so far check the three big encyclopedias.

• Kirk Othmer
• John J Mcketta
• and Ullmans

A number of references were also found using scopus/science direct and google (Google gave many results but only a few relevant ones). From what i've read these seem to give me enough information on the background to the reaction schemes i need and so far i have recovered 5 schemes to form tetraflouroethylene (TFE),C2F4, the monomer for PTFE. These schemes are given as

• Chloroform (CHCl3) + Hydrogen flouride (HF) => Flouroform (CHF3) or Chlorofdifluoromethane(CDFM) (CHFCl2) + Hydrogen chloride (HCl) => CDFM + Fluoroform are pyrolysed to TFE
• Carbon Tetraflouride (CF4) is passed through an electric arc to fomr TFE
• Fluoroacetic acid (CF3COOH) to TFE
• PTFE to TFE (The reversal of the polymerisation)
• Dibromotetraflouroethane (C2Br2F4) or Dichlorotetrafluoroethane (C2Cl2F4) to TFE by pyrolysis

From all these sources comes my first question is there any base/source i have missed that you can think of for more info on the synthessis reactions ?

Next phase in our project is to select the best process based upon the cost of the reagents and raw materials, To this end we have found information in the chemical marketing reporter* and a few places on the web but there is no good reliable source that i have found so far for this source of information, searching price lists has yielded little info and if there is it's a bit out of date typically. I have contacted one or two supply companies via e-mail but they don't care to respond. This prompts my second question: Are there any places that one can find good reliable chemical price data ? I really need help with this one and am flumoxed to say the least, searching the web for almost three days straight has only yielded the sources I mention above and a number of price indexes that incorporate an entire chemical sector and not the specific chemical prices i seek.

Next We have been shown that it is possible to determine the cost of a new plant based on an old one via pro-rating the old plant's fixed capital investment wrt to carbon steel and adjusting for the capacities required as well. I think the methods were developed by KM Guthrie and are given in Jelens’ cost accouting. I have found* the capacities for a few plants that are in existence, but i have no idea of how much capital was expended in building these plants, i understand that this could be confidential information to the company but i was wondering if there was any method of determining estimates of such values from say stock information purely for the sake of my project ? If you happen to know of any sources that should cover such information please let me know. Especially if there is a place that lists the plant cost in terms of the carbon steel price and the total price including the additional materials of construction e.g. stainless steel.

So my three biggies for now are :
1) Where can i find information on the costs for reagents ?
2) Where can i find information on the fixed capital investment required to build previous chemical plants ?
3) Is there anywhere else I could look to obtain information on the synthessis of TFE ?

Your help would be greatly appreciated, also any comments or criticisms, thanks.

Please, I don't feel i'm being a lazy student I have tried pretty hard so far to acquire as much info as possible. I say this because i have seen in some of the other posts where students have just asked without looking first and have been given negative feedback as a result, for example all the PFID Posts all run along the same theme and repeat one another, my hope is to avoid this. Further more i know i have found a lot of information that some of my fellow class mates have not, so i'm pretty certain i'm doing a good job so far.

Thanks,

Carel

* as to the little asterisks' : The Chemical marketing reporter(CMR) is no more the company was bought out or sold of the CMR to a company called ICIS, they seem to maintain it periodically and have a relatively up to date copy of the CMR price list available freely on their webiste for studetns to access. They also list a number of plants worldwide by what they produce and which company owns the plant and so on. If your as flumoxed as me go here first at least its a start for the right stuff