Recovery and Marine Clay Stabilization of Heavy Metals Present in Spent Hydrotreating Catalysts
Publication: Journal of Environmental Engineering
Volume 127, Issue 10
Abstract
This paper presents the results of an investigation on the treatment of two industrial solid wastes produced by oil refineries in Singapore, namely Ni/Mo/γAl2O3 and Co/Mo/γAl2O3. Calcination at 500°C was effective in removing carbon and sulfur in both wastes followed by generation of heavy metal oxides. A two-stage leaching process was successful in removing 44% nickel, 77% cobalt, and 83% molybdenum. However, toxicity characteristic leaching procedure leaching tests for spent catalyst residues of Co/Mo/γAl2O3 and Ni/Mo/γAl2O3 after the two-stage leaching process showed that the concentration of Mo, Co, and Ni in the leachate exceeded the allowable limits. Finally, the residues, when subjected to an enhanced binder stabilization treatment with marine clay, produced a commercial-value brick made of up to 30% by weight spent catalysts. It is believed that stabilization can be achieved through either encapsulation whereby the clay forms a matrix around the heavy metals to prevent leaching or incorporation in which the heavy metals actually become part of the stabilizing matrix.
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References
1.
Albino, V., Cioffi, R., Pansini, M., and Colella, C. ( 1995). “Disposal of lead containing zeolite sludges in cement matrix.” Envir. Technol., London, 16(2), 147–156.
2.
Cioffi, R., Pansini, M., Caputo, D., and Colella, C. ( 1996). “Evaluation of mechanical and leaching properties of cement-based solidified materials encapsulating Cd-exchange natural zeolites.” Envir. Technol., London, 17(11), 1215–1224.
3.
Conner, J. R. ( 1990). Chemical fixation and solidification of hazardous waste, Van Nostrand Reinhold, New York.
4.
Cotton, F. A., and Wilkinson, G. ( 1972). Advanced inorganic chemistry, 3rd Ed., Wiley, New York.
5.
Deltober, E., de Zoubov, N., and Pourbaix, M. ( 1974a). “Aluminium.” Atlas of electrochemical equilibria in aqueous solution, M. Pourbaix, ed., 168–176.
6.
Deltober, E., de Zoubov, N., and Pourbaix, M. ( 1974b). “Molybdenum.” Atlas of electrochemical equilibria in aqueous solution, M. Pourbaix, ed., 168–176.
7.
Deltober, E., de Zoubov, N., and Pourbaix, M. ( 1974c). “Nickel.” Atlas of electrochemical equilibria in aqueous solution, M. Pourbaix, ed., 168–176.
8.
Dion, L. B. ( 1996). “Immobilizing heavy metals in a ceramic matrix: A hazardous waste treatment technology.” Engineer thesis, Stanford University, Stanford, Calif.
9.
Habermethl, R. ( 1987). “Spent catalyst—Handling and disposal, economically and safely.” Proc., AIChE Spring Nat. Meeting.
10.
Ibanez, R., Andres, A., Irabien, J. A., and Ortiz, I. (1998). “Fly ash binders in stabilization of FGD wastes.”J. Envir. Engrg., ASCE, 124(1), 43–50.
11.
Killian, G. ( 1988). “Influencing the quality of concrete through the ultrafines content in the aggregate.” Betonwerk + Fertigteil-Technik, 75–79.
12.
Lagrega, M. D. ( 1994). Hazardous waste management, McGraw-Hill, New York.
13.
Lo, I. M.-C. (1996). “Solidification/stabilization of phenolic waste using organic-clay complex.”J. Envir. Engrg., ASCE, 122(9), 850–855.
14.
Parsa, J., Munson-McGee, S. H., and Steiner, R. (1996). “Stabilization/solidification of hazardous wastes using fly ash.”J. Envir. Engrg., ASCE, 122(10), 935–940.
15.
Rahman, S. H. ( 1994). “Real crystal structure of mullite.” Mullite and mullite ceramics, Wiley, New York.
16.
Schneider, H. ( 1990). “Transition metal distribution in mullite.” Mullite and mullite matrix composities, S. Somiya, R. F. Davis, and J. A. Pask, eds., Vol. 6, 135–158.
17.
Schneider, H., Okada, K., and Pask, J. A. ( 1994). Mullite and mullite ceramics, Wiley, New York.
18.
Sittig, M. ( 1985). Handbook of toxic and hazardous chemicals and carcinogens, Noyes Public, New York.
19.
Stein, V. ( 1982). “The raw materials for brick and tile making.” Brick and tile making—Procedures and operating practice in the heavy clay industries, W. Bender and F. Handle, eds., Bauverlag, Berlin, 73–94.
20.
Sun, D. ( 1997). “Safe disposal of spent refinery catalysts.” ETI, Nanyang Technological University, Singapore.
21.
Sun, D., Li, X. Z., Brungs, M., and Trimm, D. ( 1998). “Encapsulation of heavy metals on spent fluid catalytic cracking catalyst.” Water Sci. and Technol., 38(4–5), 217.
22.
Sun, D., Tay, J. H., and Easton, C. ( 1999). “Recovery and encapsulation of heavy metals on refinery spent hydrotreating catalyst.” Proc., Waste Minimisation and End of Pipe Treatment in Chem. and Petrochemical Industries, 277–284.
23.
Tay, J. H., Hong, S. Y., and Show, K. Y. (1999). “Reuse of industrial sludge as pelletized aggregate for concrete.”J. Envir. Engrg., ASCE, 126(3), 279–287.
24.
Trimm, D. L., Akashah, S., Absi-Halabi, M., and Bishara, A., eds. ( 1989). “Catalysts in petroleum: Refining.” Proc., Conf. on Catalysts in Petr. Refining, Elsevier Science, Amsterdam, 41–60.
25.
U.S. Environmental Protection Agency (US EPA). ( 1992). “TCLP standard test method.” Federal Register, 51(114).
26.
Velde, B. ( 1992). Introduction to clay minerals: Chemistry, origins, uses and environmental significance, Chapman & Hall, London.
27.
Weaver, C. E. ( 1989). Clays, muds and shales, Elsevier Science, New York.
28.
Webster, M. T., and Loehr, R. C. (1996). “Recycling of spent abrasive media in non-structural concrete.”J. Envir. Engrg., ASCE, 122(9), 840–849.
29.
Woodside, G. ( 1999). Hazardous materials and hazardous waste management, Wiley, New York.
30.
World Health Organization (WHO). ( 1993). “Revision of the WHO guidelines for drinking water quality.” Geneva.
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Received: Sep 12, 2000
Published online: Oct 1, 2001
Published in print: Oct 2001
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