Prem Baboo has given an excellent answer but he didn't actually describe how to set up the model.

1) Set up a reactor to consume CO and H2 with whatever kinetic assumption you believe fit you system (First order with Langmuir-Hinshelwood inhibition usually works well) - let me know if you need help with that.

2) Use the Kinetic model to calculate the amount of CO consumed ,

3) Calculate the product distribution - typically a slightly modified version of Schulz-Flory (S-F) with adjustment in the C1-C5 range, Methane is always higher than S-F would predict some chose to use an additional CO+3H2=> CH4 + H20 reaction.

The additional methane production is often modeled as a separate methanation reaction (in addition to the methane produced via F-T). This gives a little more flexibility t predict it accurately as conditions change.

The F-T reaction is often observed to appear to accelerate as the reaction proceed this apparent auto-catalysis is probably due to Langmuir-Hinshelwood inhibition by one of the reactants (the CO).

Let me know if you need additional information.

The syngas generation process and the Fischer Tropsch synthesis (FTS) process, are analyzed in detail with ASPEN Plus. The auto thermal reforming process (ATR) is analyzed using Aspen Plus based on the Gibbs reactor model, while FTS is simulated with ASPEN Plus based on detailed kinetic models for industrial iron and cobalt catalysts. Integrated GTL processes with iron and cobalt‐based catalysts were simulated using ASPEN Plus

1. The Fischer-Tropsch product component distribution is predicted by the Shulz-Flory (SF) distribution. Methane and C1-C4 are often a little higher than predicted but the fraction for heavier hydrocarbons usually adhere pretty closely to the SF distribution.

2. Diesel is typically defined as 350-700 F (180-375 C) boiling range which approximately corresponds to C10-C20 carbon numbers. The very narrow C12-C15 range you are looking for would be about 8-9% of the total product assuming alpha around 0.9.

3. The fraction of the product that boils in this range is independent of conversion however increasing temperature would likely result in a lower alpha and less C12-C15 product.

https://www.mdpi.com/1996-1073/11/2/362/pdf

Please ref to,-

https://www.researchgate.net/post/How_to_simulate_Fischer_Tropsch_Synthesis_on_Aspen_Plus

Prem Baboo has given an excellent answer but he didn't actually describe how to set up the model.

1) Set up a reactor to consume CO and H2 with whatever kinetic assumption you believe fit you system (First order with Langmuir-Hinshelwood inhibition usually works well) - let me know if you need help with that.

2) Use the Kinetic model to calculate the amount of CO consumed ,

3) Calculate the product distribution - typically a slightly modified version of Schulz-Flory (S-F) with adjustment in the C1-C5 range, Methane is always higher than S-F would predict some chose to use an additional CO+3H2=> CH4 + H20 reaction.

The additional methane production is often modeled as a separate methanation reaction (in addition to the methane produced via F-T). This gives a little more flexibility t predict it accurately as conditions change.

The F-T reaction is often observed to appear to accelerate as the reaction proceed this apparent auto-catalysis is probably due to Langmuir-Hinshelwood inhibition by one of the reactants (the CO).

Let me know if you need additional information.

Hi,

Check following books: CHEMICAL REACTOR DESIGN AND CONTROL by William L. Luyben, and Biorefineries and Chemical Processes Design, Integration and Sustainability Analysis by JHUMA SADHUKHAN et al. 2014

Good luck,

J.L

Another one of those questions that somebody asks and generates some discussion but never acknowledges any of the answers or rejoins the conversation in any way. Very strange. I guess Haseeb Tahir was desperate for some help when he asked the question but quickly figured out what he needed an forgot all about the discussion he started.

Hello @Rick Manner, apologies if I have appeared ungrateful, I am new to using researchgate. The help was greatly appreciated and the Aspen model worked. O also had a look on your profile and read some of your research which greatly eased the process

Haseeb Tahir Thanks for the reply, I am glad to hear that you are a real person and not some sort of a bot trolling for RG score points

Good day Rick Manner ,

I am hoping if you could elaborate you steps posted on the 6th March? I am stuck on step one. I am doing my final year thesis on the FT synthesis but have zero experience on modelling any kind of reactor. I have only been exposed to extraction and distillation columns...

I would think I have set up the plug flow reactor in Aspen Plus using the Langmuir-Hinshelwood Hougen Watson (LHHW) and have used the Yates and Satterfeld (1991) equation:

-Rco = (aPcoPH2)^0.5 / (1+bPco)^2

Im struggling to understand the link of how to simulate the product distribution using the Anderson-Schulz-Flory in aspen and how to lump hydrocarbons together in the component input.

Wesley Chen The entire S-F distribution is the product. You consume 2+ H2 for every CO consumed and produce the entire SF distribution of products (CH4- C infinity) the C1- C4 or C5 product does not exactly follow the SF distribution (Cx = alpha x C x-1) typically more CH4, less C2 and a leveling out to reach constant alpha by C5 or C6+. Iron catalyst will produce more olefins. Cobalt (usually with a dash of Rhenium) will typically produce nearly 100% paraffins. CH4 is always above S-F prediction some light olefins and Oxygenates are usually produced - especially with Fe based catalyst

Rick Manner thank you! Yes we are using Cobalt to produce wax and we are just looking at the RWGS and FT reactor. Can you provide some assistance with Aspen set up? Specifically with what I have read online, in terms of lumping paraffinic compounds together? Unless Aspen does it automatically and I have inputted components incorrectly or set up the reactor incorrectly.