T. Mohammed, W. and M. Zaboon, S. (2009) “Recovery of Catalyst from Tar Formed in Phenol Production Unit”, Iraqi Journal of Chemical and Petroleum Engineering, 10(3), pp. 9-17. Available at: http://ijcpe.uobaghdad.edu.iq/index.php/ijcpe/article/view/408 (Accessed: 20November2019).