LOGIN TO YOUR ACCOUNT

Username
Password
Remember Me
Or use your Academic/Social account:

CREATE AN ACCOUNT

Or use your Academic/Social account:

Congratulations!

You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.

Important!

Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message

CREATE AN ACCOUNT

Name:
Username:
Password:
Verify Password:
E-mail:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Saha, B; Mohammed, ML; Mbeleck, R (2015)
Publisher: Royal Society of Chemistry
Languages: English
Types: Article
Subjects:
The growing concern for the environment, increasingly stringent standards for the release of chemicals into the environment and economic competitiveness have prompted extensive efforts to improve chemical synthesis and manufacturing methods as well as development of new synthetic methodologies that minimise or completely eliminate pollutants. As a consequence, more and more attention has been focused on the use of safer chemicals through proper design of clean processes and products. Epoxides are key raw materials or intermediates in organic synthesis, particularly for the functionalisation of substrates and production of a wide variety of chemicals such as pharmaceuticals, plastics, paints, perfumes, food additives and adhesives. The conventional methods for the industrial production of epoxides employ either stoichiometric peracids or chlorohydrin as an oxygen source. However, both methods have serious environmental impact as the former produces an equivalent amount of acid waste, whilst the later yields chlorinated by-products and calcium chloride waste. There has been considerable effort to develop alternative alkene epoxidation methods by employing an oxidant such as tert-butyl hydroperoxide (TBHP) as it is environmentally benign, safer to handle and possesses good solubility in polar solvents. A notable industrial implementation of alkene epoxidation with TBHP was the Halcon process that employed soluble molybdenum(VI) as a catalyst for liquid phase epoxidation of propylene to propylene oxide. However, homogenous catalysed alkene epoxidation has several drawbacks including deposition of catalyst on the reactor walls and increased difficulties in separation of catalyst from the reaction mixture. In this work, an efficient and selective polystyrene 2-(aminomethyl)pyridine supported molybdenum complex (Ps.AMP.Mo) and a polybenzimidazole supported molybdenum complex (PBI.Mo) have been used as catalysts for epoxidation of 4-vinyl-1-cyclohexene (i.e. 4-VCH) using TBHP as an oxidant in batch and continuous reactors. An extensive assessment of the catalytic activity, stability and reusability of the catalysts has been conducted in a classical batch reactor. Experiments have been carried out to study the effect of reaction temperature, feed molar ratio of alkene to TBHP and catalyst loading on the yield of 1,2-epoxyhexane and 4-vinyl-1-cyclohexane 1,2-epoxide (4-VCH 1,2-epoxide) to optimise the reaction conditions in a batch reactor. A detailed evaluation of molybdenum (Mo) leaching from the polymer supported catalyst has been investigated by isolating any residue from reaction supernatant solutions and then using these residues as potential catalyst in epoxidation reactions. Furthermore, the efficiency of the heterogeneous catalyst for continuous epoxidation studies have been assessed using a FlowSyn continuous flow reactor by studying the effect of reaction temperature, feed molar ratio of alkene to TBHP and feed flow rate on the conversion of the oxidant and the yield of corresponding epoxide. The continuous flow epoxidation using FlowSyn reactor has shown considerable time savings, high reproducibility and selectivity along with remarkable improvements in catalyst stability compared to reactions carried out in a batch reactor.
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • 1 G. Sienel, R. Rieth and K. T. Rowbottom, In Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2000.
    • 2 K. Bauer, D. Garbe and Surburg, H., Common Fragrance and Flavour Materials, Wiley-VCH, Weinheim, 2001, pp. 143-145.
    • 3 A. K. Yudin, Aziridines and Epoxides in Organic Synthesis, Wiley-VCH, Weinheim, 2006, pp. 185-389.
    • 4 K. Ambroziak, R. Mbeleck, B. Saha and D. C. Sherrinton, J. Ion exchange, 2007, 18, 598-603.
    • 5 K. Ambroziak, R. Mbeleck, Y. He, B. Saha and D. C. Sherrington, Ind. Eng. Chem. Res., 2009, 48, 3293-3302.
    • 6 K. Ambroziak, R. Mbeleck, B. Saha and D. C. Sherrington, Int. J. Chem. React. Eng., 2010, 8, A125.
    • 7 R. Mbeleck, K. Ambroziak, B. Saha and D. C. Sherrington, React. Funct. Polym., 2007, 67, 1448-1457.
    • 8 M. L. Mohammed, R. Mbeleck, D. Patel, D. Niyogi, D. C. Sherrington and B. Saha, Chem. Eng. Res. Des., 2015, 94, 194-203.
    • 9 M. L. Mohammed, R. Mbeleck, D. Patel, D. C. Sherrington and B. Saha, Green Process Synth., 2014, 3, 411-418.
    • 10 D. Swern, Ed., In Organic Peroxides, Wiley Interscience, New York, 1971.
    • 11 F. Bezzo, A. Bertucco, A. Forlin and M. Barolo, Sep. Purif. Technol., 1999, 16, 251-260.
    • 12 Y. Liu, H. Tsunoyama, T. Akita and T. Tsukuda, Chem. Commun., 2010, 46, 550-552.
    • 13 B. Singh, B. S. Rana, L. N. Sivakumar, G. M. Bahuguna and A. K. Sinha, J. Porous Mat., 2013, 20, 397-405.
    • 14 J. Kollar, US Pat. 3351635, 1967.
    • 15 J. Huang, X. Fu and Q. Miao, Appl. Catal., A, 2011, 407, 163- 172.
    • 16 E. Angelescu, O. D. Pavel, R. Ionescu, R. Birjega, M. Badea and R. Zavoianu, J. Mol. Catal. A-Chem, 2012, 352, 21-30.
    • 17 U. Arnold, W. Habicht and M. Doring, Adv. Synth. Catal, 2006, 348, 142-150.
    • 18 G. R. Nath and K. Rajesh, Asian J. Chem, 2012, 24, 4548-4550.
    • 19 J. K. Satyarthi and D. Srinivas, Appl. Catal., A, 2011, 401 189- 198.
    • 20 E. Mikolajska, V. Calvino-Casilda and M. A. BaƱares, Appl. Catal., A, 2012, 421, 164-171.
    • 21 S. Hu, D. Liu, C. Wang, Y. Chen, Z. Guo, A. Borgna and Y. Yang, Appl. Catal., A, 2010, 386, 74-82.
    • 22 N. Linares, C. P. Canlas, J. Garcia-Martinez and T. J. Pinnavaia, Catal. Commun, 2014, 44, 50-53.
    • 23 Q. Jin, J. Bao, H. Sakiyama and N. Tsubaki, Res. Chem. Intermed., 2011, 37, 177-184.
    • 24 M. Sharbatdaran, F. Farzaneh and M. M. Larijani, J. Mol. Catal. A-Chem, 2014, 382, 79-85.
    • 25 K. C. Gupta and A. K. Sutar, Polym. Adv. Technol., 2008, 19, 186-200.
    • 26 S. Tangestaninejad, V. Mirkhani, M. Moghadam and G. Grivani, Catal. Commun.,2007, 8, 839-844.
    • 27 G. Grivani and A. Akherati, Inorg. Chem. Commun., 2013, 28, 90-93.
    • 28 M. L. Mohammed, D. Patel, R. Mbeleck, D. Niyogi, D. C. Sherrington and B. Saha, Appl. Catal., A, 2013, 466, 142-152.
  • No related research data.
  • Discovered through pilot similarity algorithms. Send us your feedback.

Share - Bookmark

Cite this article