1. Discipline of Inorganic Materials and Catalysis, Central Salt & Marine Chemicals Research Institute, G. B. Marg, Bhavnagar 364 002, Gujarat, India, Department of Chemistry, Veer Narmad South Gujarat University, Surat 395 007, Gujarat, India, Chemical Engineering Department, Sardar Vallabhbhai National Institute of Technology, Surat 395 007, Gujarat, India, and R & D Centre, Reliance Industries Limited, Vadodara Manufacturing Division, Vadodara, 391 346, Gujarat, India