Acknowledgements
We would like to thank the critical reviews of Dr Rama K. Kotra
and Dr William H. Orem of the U. S. Geological Survey, Prof.
Chunmian Lin and Prof. Yinfei Chen of Zhejiang University
of Technology, and also three anonymous reviewers. Financial
support for this work was provided by National Natural Science
Foundation of China (No. 20677052 and No. 20777070) and
the Energy Program of US Geological Survey. The use of trade,
product, industry, or firm names in this report is for descriptive
purposes only and does not constitute endorsement by the US
government.
Notes and references
1 A. L. Bisio and M. Xanthos, How to Manage Plastics Waste, Hanser
Publishers, New York, 1995.
2 (a) B. Singh and N. Sharma, Polym. Degrad. Stab., 2008, 93, 561;
(b) M. Goto, M. Sasaki and T. Hirose, J. Mater. Sci., 2006, 41, 1509.
3 (a) H. Weingartner and E. U. Franck, Angew. Chem., Int. Ed., 2005,
44, 2672; (b) P. E. Savage, Chem. Rev., 1999, 99, 603; (c) P. E. Savage,
S. Gopalan, T. I. Mizan, C. J. Martino and E. E. Brock, AlChE J.,
1995, 41, 1723.
4 (a) R. Marr and T. Gamse, Chem. Eng. Process., 2000, 39, 19; (b) R. H.
Jason, P. Licence, D. Carter and M. Poliakoff, Appl. Catal., A, 2001,
222, 119; (c) S. Pereda, S. B. Bottini and E. A. Brignole, Appl. Catal.,
A, 2005, 281, 129; (d) W. X. Wang, S. M. Howdle and D. Y. Yan,
Chem. Commun., 2005, 3939; (e) C. Aymonier, A. L. Serani, H.
Reveron, Y. Garrabos and F. Cansell, J. Supercrit. Fluids, 2006, 38,
242; (f) G. Maayan, B. Ganchegui, W. Leitner and R. Neumann,
Chem. Commun., 2006, 2230; (g) P. H. L. Moquin and F. Temelli,
J. Supercrit. Fluids, 2008, 45, 94; (h) A. A. Peterson, F. Vogel, R. P.
Lachance, M. Fro˝ling, M. J. Antal, Jr. Tester and J. W. Tester, Energy
Environ. Sci., 2008, 1, 33.
5 H. Tagaya, K. Katoh, J. I. Kadokawa and K. Chiba, Polym. Degrad.
Stab., 1999, 64, 289.
6 J. Huang, K. Huang, Q. Zhou, L. Chen, Y. Q. Wu and Z. B. Zhu,
Polym. Degrad. Stab., 2006, 91, 2307.
7 G. Sivalingam and G. Madras, Ind. Eng. Chem. Res., 2002, 41,
5337.
8 Z. Y. Pan, Z. Bao and Y. X. Chen, Chin. Chem. Lett., 2006, 17, 545.
9 L. C. Hu, A. Oku and E. Yamada, Polymer, 1998, 39, 3841.
10 R. Pinero, J. Garcia and M. J. Cocero, Green Chem., 2005, 7, 380.
11 (a) S. M. Howdle, K. Stanley, V. K. Popov and V. N. Bagratashvili,
Appl. Spectrosc., 1994, 48, 214; (b) S. M. Howdle and S. P. Best,
J. Raman Spectrosc., 1993, 24, 443.
12 (a) I. M. Chou, Y. C. Song and R. C. Burruss, Geochim. Cosmochim.
Acta, 2008, 72, 5217; (b) I. M. Chou, R. C. Burruss and W. J. Lu,
Advances in High-Pressure Technology for Geophysical Applications,
2005, 475.
Scheme 2 Mechanism of PC hydrolysis in sub-critical water.
In summary, a new method for studying hydrolysis of PC
in sub-critical water in FSCR was developed. in situ Raman
spectroscopy was used to analyze the products qualitatively and
quantitatively. During hydrolysis of PC, the phase behavior was
observed under a microscope and the images were recorded in a
DVD recorder continuously. Quenched products extracted from
the FSCR were also analyzed by GC and GC-MS.
Our results showed that (1) during the hydrolysis of PC in
sub-critical water at 553 K, BPA was the only product detected
in the liquid phase, (2) CO2 was the only gas product, (3) the
hydrolysis was a heterogeneous (liquid–liquid phase) reaction,
and appeared to be a self-catalytic hydrolysis or promoted by
the breakup of long-chain polymer in the near-critical water,
and (4) the hydrolysis was influenced by temperature intensively.
The new method has great advantages for studying chemical
reactions in fluids at sub- or super-critical conditions, because
(1) by using optically transparent capillary, the phase behavior
can be observed and recorded, and reaction progress can be
measured by Raman spectroscopy in situ; (2) due to the small
size of reactor, it minimizes the resistances in mass transfer and
heat transfer, such that the observed kinetics approaches to the
intrinsic one, and (3) the volume of FSCR is much smaller than
that of the autoclave (millilitre vs microlitre), so that it is safer
and more environmentally friendly due to the smaller amount
of material needed in the FSCR.
13 Z. Duan and R. Sun, Chem. Geol., 2003, 193, 257.
14 J. C. Seitz, J. D. Pasteris and I. M. Chou, Am. J. Sci., 1996, 296,
577.
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The Royal Society of Chemistry 2009
Green Chem., 2009, 11, 1105–1107 | 1107
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