Loading...

Nano-Zeolite Synthesis Adsorbents for Removal of Mercaptanes from the Butane and the Propane

Khosravanian, Abdollah | 2016

702 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 48389 (06)
  4. University: Sharif University of Technology
  5. Department: Chemical and Petroleum Engineering
  6. Advisor(s): Soltanieh, Mohammad; Shayegh, Flora; Soltanali, Saeed
  7. Abstract:
  8. In this study nano zeolite was hydrothermally synthesized in order to remove ethyl and methyl mercaptans from propane and butane stream. Fifteen experimental runs were conducted using D-Optimal method experimental design to synthesize NaY, NaX and NaA zeolites. The products were characterized by measuring the morphology, particle and crystal size, surface area, adsorption isotherm, pore size, and pore volume of the products by XRD, FE-SEM, TEM and BET analyses. The pore size for NaA type zeolites is about 4 Angstrom whereas the molecular size for ethyl mercaptan and methyl mercaptan is between 4 and 5 Angtrom, Therefore, NaA zeolite is inappropriate for removing ethyl and methyl mercaptans because the zeolite pore size should be about larger than twice the size of adsorbing molecule. Patent analysis was also conducted in order to identify the importance of NaY zeolite. The results showed that NaY zeolite is very useful in many industries such as adsorption, hydro cracking, purification etc. It was shown that the number of patents on synthesis and application of NaY zeolite has been increasing in recent years. The reason for this increasing interest in NaY is due to high surface area, high stability, appropriate pore volume and pore size of this kind of zeolite. From the patent analysis NaY zeolite was selected as an adsorbent to remove ethyl and methyl mercaptan from propane and butane stream. Three different sizes of NaY zeolite (60nm, 800nm, 2400nm) were selected to specify the effect of particle size on mercaptan’s removal performane. The inlet sour gas streams were provided from Assaluyeh which contained pure propane with 450ppm total sulfur compounds (ethyl & methyl mercaptan) and pure butane with 1100ppm total sulfur compounds (ethyl & methyl mercaptan). In the adsorption system the temperature was 90 °C and the pressure was 1 atm. The outlet gas streams were characterized using Potentiometric method (UOP212) and breakthrough curves were plotted for each stream and adsorbent. The results from outlet gas analysis indicate that the zeolite with 60nm particle size showed the best performance for both of inlet streams. Finally the breakthrough curves were modeled using BDST (bed depth service time) model and Yoon-Nelson model
  9. Keywords:
  10. Nanozeolite ; Absorption ; Demercaptanization ; Propane ; Butane ; Nanoadsorbent

 Digital Object List

 Bookmark

No TOC