SBIR Phase II: Employing a New Class of Chemosensors for Continuous, Real-Time Measurement of Heavy Metals in Wastewater

这个小型企业创新研究（SBIR）二期项目使用一种新型化学传感器薄膜来连续测量工业废水中重金属的浓度。这将使人们有可能知道在任何给定时间几种重金属的浓度，从而可以精确地测量用于去除这些金属的处理化学品。目前的处理方法通常依赖于不频繁的废水流采样和时间延迟，劳动密集型的实验室测量。由于没有连续测量的能力，废水处理是根据周期性平均值和估计的峰值排放来调整的。为了减少违反法规的风险，大多数废水处理系统使用的处理化学品量是正常情况下所需量的两倍。具有连续自动测量金属浓度的能力，可以实时控制废水处理，将处理化学品成本，固体废物成本和测量人工成本降低50%以上。持续测量还可以将违反法规的风险降低90%，从而降低补救和合规的潜在成本，并改善公众的环境条件。第一阶段研究的关键成果是成功开发了15种新型化学传感器，这些化学传感器与基板永久结合，每种化学传感器对锌、镉、钴、铬、铅、铜、铁、镁、锰、汞、镍和锡都有独特的反应。在第二阶段，一系列化学传感器的响应将通过为不同工业环境的商业用途而开发的原型仪器进行充分表征。有了该仪器，将建立一个数学模型，以准确地将传感器响应转换为多种溶解金属的科学测量单位。现有传感器的检测下限为5ppb至50ppb。与分析建模工作并行，化学传感器合成工作继续将检测极限降低到1 ppb，将传感器寿命延长到6个月以上，并扩大传感器的组合以提高金属选择性。在未来，这种新型键合化学传感器可能会扩展到确定磷酸盐和许多其他物质的浓度，这些物质目前偶尔取样并使用实验室仪器测量。对于连续测量很重要的应用，这种独特的化学传感器系列为各种工业应用中的实时过程控制提供了巨大的潜力。

This Small Business Innovation Research (SBIR) Phase II project uses a new class of chemosensor films to continuously measure the concentration of heavy metals in a flowing stream of industrial wastewater. This will make it possible to know the concentration of several heavy metals at any given time so that treatment chemicals used to remove those metals can be metered precisely. Current treatment methods typically rely on infrequent sampling of wastewater streams and time-delayed, labor-intensive laboratory measurements. Without the ability to measure continuously, wastewater treatment is adjusted based on periodic averages and estimated peak discharges. To reduce the risk of regulatory violation, most wastewater treatment systems use twice the volume of treatment chemicals than might otherwise be needed. With the ability to measure metal concentrations continuously and automatically, wastewater treatment can be controlled in real time, cutting treatment chemical costs, solid waste costs and measurement labor costs by more than 50%. Continuous measurement also reduces the risk of regulatory violations by 90%, in turn reducing the potential costs of remediation and compliance as well as improving environmental conditions for the general public. The key outcome of Phase I research was the successful development of 15 new chemosensors permanently bound to a substrate, each with a unique response to zinc, cadmium, cobalt, chromium, lead, copper, iron, magnesium, manganese, mercury, nickel and tin. In Phase II, responses from an array of chemosensors will be fully characterized with a prototype instrument developed for commercial use in different industrial environments. With that instrument, a mathematical model will be constructed to accurately convert sensor responses into scientific units of measure for multiple dissolved metals. The lower limit of detection for existing sensors ranges from 5 ppb to 50 ppb. In parallel with analytical modeling work, chemosensor synthesis work continues to lower the limit of detection to 1 ppb, extend sensor life beyond 6 months, and broaden the portfolio of sensors to improve metal selectivity. In the future, this new class of bonded chemosensors may be extended to determine the concentration of phosphates and many other species that are currently sampled occasionally and measured with lab instruments. For applications where continuous measurement is important, this unique family of chemosensors offers great potential for real-time process control in a variety of industrial applications.