An Electrochemical Approach to Study Carbonation of Novel Lime Based Materials

研究新型石灰基材料碳化的电化学方法

• 批准号: EP/I001204/1
• 负责人: Richard Ball
• 金额: $ 17.64万
• 依托单位: University of Bath
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2010
• 资助国家: 英国
• 起止时间: 2010 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FI001204%2F1
• 关键词: Electrochemical; Approach; Study; Carbonation; Novel

This project seeks to advance the current understanding of carbonation in lime and cement materials. A novel approach is proposed where the reaction with carbon dioxide will be studied using micro pH electrodes. pH variations in a thin water film at the sample surface will allow the reaction mechanism to be determined. A detailed understanding of the surface morphology and composition will be provided by a comprehensive electron optical and surface analytical study. The reaction of these materials with carbon dioxide is or great interest as sequestration of carbon dioxide is a key initiative aimed at reducing climate change. Lime has the ability to adsorb significantly higher quantities of carbon dioxide during the setting process in comparison to alternative products such as cement and has important applications in the restoration and conservation of historic buildings in addition to renovation and new build projects. Cement acquires its strength from hydration of reactive silicate and aluminate clinker phases however in the long term carbonation of these phases can lead to a reduction in mechanical performance and the corrosion of steel reinforcements if present.Although the chemical process of carbonation is well known the mechanisms in lime and cement mortars are poorly understood. This research programme seeks to address this issue.In recent years the producers of low carbon footprint materials such as hemp and wastes from a range of industrial processes have expressed interest in the incorporation of their materials as fillers and additives in lime and cement products including mortars, renders, plasters and concrete. The addition of these environmentally friendly materials not only influence the micro and macro pore structure but soluble constituents may introduce ionic species into the pore water, the influence of which on carbonation is unknown. This proposal aims to study the carbonation process by monitoring ion concentrations at different locations within the liquid film on the surface of a calcium hydroxide substrate. Proton concentrations will be measured using specially manufactured microelectrodes consisting of nanostructured palladium hydride discs approximately 10 micrometers in diameter and electrodeposited on the end of a normal microdisc electrode. Held precisely with a micropositioner the pH microelectrode will be brought to within a few micrometres from the surface under investigation. In a similar way, commercially available ion selective electrodes will be used to determine the calcium ion concentration. In the second phase of the project the effect of ions leached from additives commonly used in conjunction with lime will be investigated. These can be divided into the following five groups, blast furnace slag (GGBS), bottle glass, wood ash, hemp and metakaolin.Additives of interest will include glass, ashes / slag and organic surfactants.

该项目旨在推进目前对石灰和水泥材料碳化的理解。提出了一种新的方法，其中与二氧化碳的反应将使用微pH电极进行研究。在样品表面的薄水膜的pH值的变化将允许的反应机制被确定。通过全面的电子光学和表面分析研究，将提供对表面形态和组成的详细了解。这些材料与二氧化碳的反应非常有趣，因为二氧化碳的封存是旨在减少气候变化的关键举措。与水泥等替代产品相比，石灰在凝固过程中能够吸附大量的二氧化碳，并且除了翻新和新建项目外，还在历史建筑的修复和保护方面具有重要应用。水泥的强度来自于活性硅酸盐和铝酸盐熟料相的水化，然而，长期来看，这些相的碳酸化会导致机械性能的降低和钢筋的腐蚀（如果存在的话）。近年来，大麻等低碳足迹材料的生产商和一系列工业过程中产生的废物表示有兴趣将其材料作为填料和添加剂加入石灰和水泥产品，包括砂浆、抹灰、石膏和混凝土。这些环境友好材料的添加不仅影响微观和宏观孔结构，而且可溶性成分可能将离子物质引入孔隙水中，其对碳酸化的影响是未知的。该提案旨在通过监测氢氧化钙基质表面上的液膜内不同位置处的离子浓度来研究碳酸化过程。将使用专门制造的微电极测量质子浓度，微电极由直径约10微米的纳米结构氢化钯盘组成，并电沉积在正常微盘电极的末端。用微定位器精确地固定pH微电极，将其带到离被研究表面几微米的范围内。以类似的方式，市售的离子选择性电极将用于测定钙离子浓度。在该项目的第二阶段，将研究从通常与石灰一起使用的添加剂中浸出的离子的影响。这些添加剂可分为以下五类：高炉矿渣（GGBS）、瓶玻璃、木灰、大麻和偏高岭土。

项目成果

Monitoring hydration in lime - metakaolin composites

监测石灰-偏高岭土复合材料的水合作用

• 作者: Giovanni Luca Pesce (Author)

Monitoring Hydration In Lime-Metakaolin Composites Using Electrochemical Impedance Spectroscopy And Nuclear Magnetic Resonance Spectroscopy

• DOI: 10.1180/claymin.2014.049.3.01
• 发表时间: 2014-06
• 期刊: Clay Minerals
• 影响因子: 1.5
• 作者: G. Pesce;C. Bowen;J. Rocha;M. Sardo;G. C. Allen;P. Walker;G. Denuault;M. Serrapede;R. Ball

Factors affecting the water retaining characteristics of lime and cement mortars in the freshly-mixed state

新拌状态石灰水泥砂浆保水特性的影响因素

• DOI: 10.1617/s11527-010-9645-1
• 发表时间: 2010
• 期刊: Materials and Structures
• 影响因子: 3.8
• 作者: Ince C

Radiocarbon Dating of Mortars from the Baptismal Font of the San Lorenzo Cathedral of Alba (Cuneo, Italy): Comparison with the Thermoluminescence Dating of Related Bricks and Pipes

阿尔巴圣洛伦索大教堂（意大利库尼奥）洗礼池的迫击炮放射性碳测年：与相关砖块和管道的热释光测年的比较

• DOI: 10.2458/azu_js_rc.55.16299
• 发表时间: 2013
• 期刊: Radiocarbon
• 影响因子: 8.3
• 作者: Pesce G

Impedance spectroscopy measurements to study physio-chemical processes in lime-based composites

• DOI: 10.1007/s00339-011-6509-7
• 发表时间: 2011-07
• 期刊: Applied Physics A
• 作者: R. Ball;G. C. Allen;G. Starrs;W. McCarter