Development of green corrosion inhibitors for absorption-based CO2 capture processes

在使用烷醇胺水溶液的二氧化碳吸收过程中，腐蚀是最严重的操作问题之一，特别是当碳钢用于工厂建设时。为了将这种严重的腐蚀抑制到可接受的水平，腐蚀抑制剂被广泛应用于这一过程。然而，目前的腐蚀抑制剂是重金属，具有固有的毒性，可能对人类健康和环境造成不利影响。由于有关化学品使用和处置的环境法规，处理此类有毒缓蚀剂和处置工艺废物受到限制且成本高昂。现在必须发现新的环境可接受的缓蚀剂，为工业提供替代品。因此，本研究的最终目标是开发具有成本效益的绿色缓蚀剂，并为已开发的绿色缓蚀剂的有效应用建立最佳实践或策略。该研究分为三个主要任务：1)潜在绿色缓蚀剂的理论筛选和配方，2)配方缓蚀剂的性能评估，以及3)开发绿色缓蚀剂体系的预测和机理腐蚀模型。开发的绿色缓蚀剂以及有效的缓蚀剂应用策略将随时可用，以响应环境法规和工业需求。这些抑制剂有望取代目前的重金属抑制剂，从而降低废物处理成本和健康风险。这将为加拿大提供一个在绿色化学品使用领域发挥领导作用的机会。此外，从业者，特别是工艺工程师，将能够在设计和操作二氧化碳捕集过程的策略中考虑开发的绿色缓蚀剂，以减少能源消耗和溶液循环速率或工艺设备的尺寸。这将大大节省二氧化碳捕获的资本和运营成本，否则将受到腐蚀问题的限制。这将使二氧化碳捕获更加经济和环保。

Corrosion is one of the most severe operational problems in the carbon dioxide (CO2) absorption process using aqueous solutions of alkanolamines, especially when carbon steel is used for plant construction. To suppress such severe corrosion to an acceptable level, corrosion inhibitors are widely applied to this process. However, current corrosion inhibitors are heavy metals that are inherently toxic and potentially pose adverse impacts on human health and the environment. Due to the environmental regulations on the chemical use and disposal, handling of such toxic corrosion inhibitors and disposal of the process waste are restricted and costly. New corrosion inhibitors which are environmentally acceptable must now be discovered to provide alternatives to industry. The ultimate objectives of this proposed research are therefore to develop cost-effective green corrosion inhibitors and establish best practices or strategy for an effective application of the developed green corrosion inhibitors. The proposed research is divided into three main tasks: 1) theoretical screening and formulations of potential green corrosion inhibitors, 2) performance evaluation of the formulated inhibitors, and 3) development of a predictive and mechanistic corrosion model for the green inhibitor system. The developed green corrosion inhibitors together with the strategy for effective inhibitor application will be readily available in response to environmental regulations and industrial needs. These inhibitors are expected to replace current heavy metal inhibitors, thus reducing cost of waste disposal and health risk. This would present an opportunity for Canada to take a leadership role in the area of green chemical use. In addition, practitioners, especially process engineers, would be able to factor in the developed green corrosion inhibitors in their strategy for the design and operation of CO2 capture processes to reduce energy consumption and solution circulating rate or size of process equipment. This would lead to significant savings in both capital and operating costs for CO2 capture, which are otherwise limited by corrosion problems. This would make CO2 capture more economical and environmentally favorable.