{'fraction_non_alphanumeric': 0.04509090909090909, 'fraction_numerical': 0.05018181818181818, 'mean_word_length': 3.8280701754385964, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Metal Sulfate Catalyst for CCl2F2 Decomposition in the Presence of H2O

Activities for the hydrolysis of CCl 2 F 2 (CFC-12) on various metal sulfates were investigated in this study. It was found that Zr(SO 4 ) 2 exhibits a high activity for CFC-12 decomposition and a high selectivity to CO 2 . On the other hand, the metal sulfates Al 2 (SO 4 ) 3 , La 2 (SO 4 ) 3 , Ce 2 (SO 4 ) 3 , and Cr 2 (SO 4 ) 3 were also active for the hydrolysis of CFC-12. However, the activities for CFC-12 decomposition of MnSO 4 , CoSO 4 , and MgSO 4 were low, and decomposition of CFC-12 hardly occurred on the metal sulfates CaSO 4 , SrSO 4 , and BaSO 4 . Among the investigated metal sulfates, Zr(SO 4 ) 2 was the most active, and the complete decomposition of CFC-12 was achieved at 598 K. The CFC-12 decomposition rate monotonically increased with increasing CFC-12 partial pressure. On the other hand, CFC-12 conversion became highest at an oxygen content of 18.9 mol% and a H 2 O content of 5 mol%. Therefore, the main reaction on Zr(SO 4 ) 2 for CFC-12 decomposition into CO 2 and HCl and HF is the hydrolysis reaction. The high activity to CFC-12 decomposition on Zr(SO 4 ) 2 was stably sustained over the 40-h period examined. Therefore, the metal sulfate Zr(SO 4 ) 2 is highly active for the hydrolysis of CFC-12 and has sufficient stability against fluorination and/or chlorination.