| 摘要: |
| 系统研究了在高压汞灯或天然日光照射下萘在天然海水、人工海水和蒸馏水中的光降解情况。萘的光降解过程受到包括光源、溶液介质、溶解氧、重金属离子、光敏剂在内的各种因素的影响。实验证明,高压汞灯较天然日光更能有效地激发萘的光反应。开始的90 min之内,萘的浓度慢慢下降,在照射90—120 min后,萘的浓度迅速下降,这是整个萘光解过程中最有效的部分,一级反应速率常数为0.0075—0.0203 min-1。萘在天然海水中的光解速率大于在人工海水和蒸馏水中的光解速率,其主要原因是天然海水中存在天然光敏剂。同蒸馏水中的光反应相比,人工海水中的离子有助于提高萘的光解反应。然而,溶液中加入的重金属离子或光敏剂会改变萘的光解反应。此外,研究证明,溶解氧是必不可少的,它的存在大大加速了光反应。
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| 关键词: 萘,光化学降解,海水,重金属离子,光敏剂 |
| DOI：10.11693/hyhz200301008008 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目,49706070号及40176023号;山东省自然科学基金资助项目,Q97E04145号 |
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| STUDY ON PHOTOCHEMICAL DEGRADATION OF NAPHTHALENE IN SEAWATER |
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YANG Gui-Peng, QI Jia-Lin
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College of Chemistry and Chemical Engineering, China Ocean University
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| Abstract: |
| The photochemical degradation of naphthalene was studied systematically in seawater, artificial seawater and distilled water under the radiation of high-pressure mercury lamp or sunlight. The photolysis of naphthalene was influenced by various factors including lightsource, solutionmedia, dissolved oxygen, heavy metal ions and photosensitizers. High-pressure mercury lamps were more effective for exciting the photoreaction of naphthalene relative to sunlight. The concentration of naphthalene decreased slowly for the first 90 min, followed by a period of rapid decline from 90—120 min which exhibited first-order reaction kinetic behavior with the rate constants of photolysis ranging between 0.0075 and 0.0203 min-1. The photolysis of naphthalene was faster in natural seawater than in artificial seawater or distilled water, presumably due to the existence of natural photosensitizer in seawater. Compared with the photoreaction in distilled water, the ions in artificial seawater could enhance the photolysis of naphthalene. However, some changes occurred in the effects of solution media on the photodegradation of naphthalene after the addition of heavy metal ions or photosensitizer. Furthermore, the presence of dissolved oxygen was necessary for, and largely accelerated, the photolysis of naphthalene.
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| Key words: Naphthalene,Photochemical Degradation,Seawater,Heavymetal ion,Photosensitizer |
