Analysing the effectiveness of the DB Gold cylinder passivation treatment using ultra-low amount fraction gas stability studies

在气体分析中，影响测量精度的两个重要方面是参考物质和取样。标准物质和样品都储存在高压容器中，通常是铝容器。然而，铝的表面结构会导致气体混合物中某些物质的反应或吸附。特别是，反应性和“粘性”的物种会在未经处理的圆柱体中腐烂。这可以改变气缸中成分的量，因此当测量气体时，结果将与预期的不同。当测量样品中的杂质时，这可能会导致假阳性读数。钝化是对表面进行处理或涂覆以降低化学反应性的过程。EffecTech开发了一种钝化技术（DB Gold），该技术覆盖在铝圆柱体的内表面，以减少化学反应和表面吸附。这些钢瓶可用于各种气体分析应用，包括用于燃料电池汽车的氢纯度分析和大气二氧化碳监测。然而，气瓶应使用代表性混合物进行评估，并且需要测量混合物随时间的稳定性。EffecTech没有能力制备这些气体混合物，也没有分析仪器来测量其成分。NPL是英国的国家计量研究所。他们拥有世界领先的设施，用于制备具有挑战性的气体混合物，并使用最先进的仪器进行分析。在这个项目中，我们将与国家物理实验室合作，在钝化钢瓶中测试各种具有挑战性的气体混合物的稳定性。该结果将使EffecTech能够增加钝化气缸的销售并进入新市场。此外，国家物理实验室可以使用这些数据来改进自己的标准。钝化钢瓶的最终用户，如分析实验室，将受益于更稳定的混合物，延长保质期，更高的测量精度和更低的不确定度。该A4I项目符合政府到2050年实现碳中和的政策，促进了英国能源和运输部门向脱碳和氢经济的过渡。此外，与其他钝化相比，DB Gold在处理过程中不需要有害化学物质，因此更具可持续性和环保性。

In gas analysis, two important areas that affect measurement accuracy are reference materials and sampling. Both reference materials and samples are stored in high pressure vessels, normally aluminium. However, the aluminium surface structure can lead to reaction or adsorption of certain species in a gas mixture. In particular, reactive and "sticky" species will decay in an untreated cylinder. This can alter the amount of the component in the cylinder so when it comes to measuring the gas, the result will be different from what is expected. When measuring impurities in a sample, this may result in a false positive reading.Passivation is the process of treating or coating a surface to reduce the chemical reactivity. EffecTech has developed a passivation technique (DB Gold) which coats the internal surface of aluminium cylinders in order to reduce chemical reactions and surface adsorption. These cylinders could be used in a variety of gas analysis applications, including purity analysis of hydrogen for fuel cells vehicles and atmospheric monitoring of CO2\. However, the cylinders should be evaluated using representative mixtures and the stability of the mixtures over time needs to be measured. EffecTech does not have the capability to prepare these gas mixtures nor the analytical instrumentation to measure the composition.NPL are the national metrology institute for the UK. They have world leading facilities for the preparation of challenging gas mixtures and analysis using state of the art instrumentation. In this project we will collaborate with NPL by testing stability of a variety of challenging gas mixtures in the passivated cylinders. The results will allow EffecTech to grow the passivated cylinder sales and enter new markets. Additionally, NPL can use the data to make improvements to their own standards. End users of passivated cylinders, such as analytical laboratories, will benefit from more stable mixtures in the way of increased shelf life, greater measurement precision and lower uncertainties.This A4I project aligns well with government policy to be carbon neutral by 2050, facilitating the transition of the UK energy and transport sector towards decarbonisation and a hydrogen economy. Additionally, compared to other passivations, DB Gold does not require harmful chemicals during treatment and is therefore more sustainable and environmentally friendly.