Retardation of Portland Cement Hydration with Photosynthetic Algal Biomass
Retardation of Portland Cement Hydration with Photosynthetic Algal Biomass
复制标题
DOI：
10.1021/acssuschemeng.1c04033
复制
发表时间：
2021-10-07
影响因子：
8.4
通讯作者：
Srubar, Wil V., III
中科院分区：
文献类型：
--
作者：
Chen, Xu;Matar, Mohammad G.;Srubar, Wil V., III
在这项工作中，原藻类生物质对波特兰水泥的水化动力学的影响。具体而言，直接添加0.3%、0.5%、1.0%和3.0%的光合小球藻藻类生物质到水泥浆中显著延迟了水泥水化，如通过等温量热法测量的放热主峰延迟16.5%、29.4%、82.4%和812%所示。通过FTIR证实，延迟是由原藻中-COOH和-OH官能团的存在引起的。我们证实的观察，消除-COOH和-OH官能团的藻类，通过热处理正好在延迟效果的消失，而通过H2 O2处理这些官能团的增强诱导进一步的延迟。此外，未处理和处理的藻类的形态，矿物学和抗压强度的水泥浆含有0.5%的小球藻的影响被认为是可以忽略不计的。添加0.5%的藻类生物质估计成本约为1.6 -2.6美元/m3的混凝土，这表明生藻类可以用作波特兰水泥基材料的可再生的、具有成本竞争力的、CO2储存的缓凝外加剂。
In this work, the effects of raw algal biomass on the hydration kinetics of portland cement are reported. Specifically, direct addition of 0.3%, 0.5%, 1.0%, and 3.0% photosynthetic Chlorella algal biomass to cement paste substantially delayed cement hydration, as indicated by 16.5%, 29.4%, 82.4%, and 812% delays in the main peak of heat evolution measured by isothermal calorimetry. Retardation was confirmed via FTIR to be mechanistically caused by the existence of -COOH and -OH functional groups in raw algae. We substantiated the observation that elimination of -COOH and -OH functional groups in the algae through heat treatment coincided with the disappearance in the retardation effect, while enhancement of these functional groups through H2O2 treatment induced further retardation. In addition, the effects of untreated and treated algae on the morphology, mineralogy, and compressive strength of cement pastes containing 0.5% Chlorella were found to be negligible. An addition of 0.5% algal biomass is estimated to cost approximately USD $1.6-2.6/m(3) of concrete, suggesting that raw algae could be used as a renewable, cost-competitive, CO2-storing set-retarding admixture for portland cement-based materials.