海水中COD光催化在线消解方法与消解模块研究及在线监测仪器的研制

化学需氧量（COD）是海洋生态污染综合评价和水质监测必测指标。目前，由于高温消解技术难以突破，导致海水中COD分析方法与监测仪器测定周期长、稳定性差、能耗高、应用受限，已难以满足日益增长的海洋生态环境监测的需求。本项目拟将常温常压下可快速高效氧化有机物的半导体光催化氧化技术用于COD的消解，通过半导体改性、电子捕获、光电催化等多技术耦合与提升，开展消解速率快、监测灵敏度高、能耗低的光催化氧化在线消解方法研究与在线消解模块的研制，突破COD测定中提高样品消解速率的“瓶颈”。在此基础上，结合流动注射技术与盐度补偿校正模型，开发能够快速、灵敏、准确测定海水中COD的在线监测新方法与新仪器，使之广泛应用于实验室、船载、浮标、岸基台站等大批量样品与实时样品的分析监测，满足快速发展的海洋环境监测需求，支撑海洋经济可持续发展。本研究成果顺利实施，可使海水中COD自动在线监测上一个新的台阶，引领科技前沿。

Chemical oxygen demand (COD) is the comprehensive evaluation index of marine ecological pollution and the necessary evaluation index of water quality monitoring. At present, the COD analysis methods and monitoring instruments have these disadvantages of long measuring period, poor stability,high power consumption and limited application caused by high temperature digestion, which could hardly meet the increasing demands of marine ecological environment monitoring. The study intends to apply the semiconductor photocatalytic oxidation technology, which can oxidize organic matter rapidly and efficiently under norman temperature and pressure, to the COD digestion. Through the research on the coupling and upgrading of photocatalytic oxidation technologies, such as semiconductor modification, electron capture and Photoelectricity, the new on-line digestion method of seawater COD with fast digestion rate, high monitoring sensitivity and low energy consumption is established and the on-line digestion module is developed to break through the bottleneck of low COD digestion rate. Combined with flow injection analysis and salinity compensation correction model, a new on-line monitoring method and instrument can be developed for rapid, sensitive and accurate determination of COD in seawater, which can be widely used in the on-line analysis and monitoring of large quantities of samples and real-time samples such as laboratories, surveys, buoys and shore-based stations to meet the increasing demands of marine ecological environment monitoring and to support the sustainable development of marine economy. The successful implementation of this research can promote the automatic on-line monitoring of seawater COD to a new level, and lead the scientific and technological frontier.