在化学攻击下Pb固化/稳定中,NaOH活性化和Na2SiO3活性化地质聚合物的比较耐用性
Xiyao Zheng1, Liang Li1, Guanglei Yu1
1Key Laboratory of Urban Security and Disaster Engineering, Beijing Univ. of Technology, Ministry of Education, Beijing 100124, China.
Environmental research
|March 14, 2026
概括
一部分地质聚合物有效地固定了 (Pb) 污染. 与酸激活地质聚合物 (NSG) 相比,NaOH激活地质聚合物 (NHG) 对化学攻击具有优越的长期耐用性,保持低Pb出.
科学领域:
- 地质化学和材料科学 材料科学
- 环境工程与修复工程
背景情况:
- 工业发展和污染现场的再利用增加了 (Pb) 污染的风险.
- 固化和稳定 (S/S) 固定了Pb,但在化学攻击下,单部分地质聚合物的长期耐用性需要进一步研究.
- 一部分地质聚合物在S/S应用中比两部分系统提供了安全性和实用性的优势.
研究的目的:
- 在各种化学条件下评估一部分NaOH激活地质聚合物 (NHG) 和Na2SiO3激活地质聚合物 (NSG) 的Pb固定性能和长期耐用性.
- 为了比较NHG和NSG结合物的化学抗性和微观结构演变.
主要方法:
- 合成的Pb-dopedNHG和NSG来自地面颗粒高炉渣和飞灰.
- 沉浸在H2SO4,HCl,Na2SO4和NaCl溶液中的标本,用水浸泡作为对照.
- 通过宏观的外观,质量损失,不受限制的压力强度 (UCS),耐久系数和Pb浸出来评估耐久性;使用SEM-EDS分析微观结构.
主要成果:
- 化学侵蚀的严重程度跟随H2SO4 > HCl > Na2SO4 > NaCl,其离子攻击性为H+ > SO42- > Cl- > Na+.
- NSG最初的UCS较高,但NHG在化学攻击下,特别是酸性条件下,表现出优越的长期耐用性和UCS保留.
- 在所有测试条件下,Pb液保持在5 mg/L以下,这表明Pb被两种地质聚合物类型有效固定.
结论:
- 由于其优越的耐用性和稳定的C-S-H凝结构,NHG在长期Pb固定中表现出更好的综合性能.
- 在化学攻击下,NSG的N-A-S-H凝结构导致UCS降解速度更快.
- NHG和NSG都是Pb固定的可行的结合剂,但NHG更适用于需要增强长期化学耐药性的应用.
更多相关视频
11:14Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
13.0K
10:53Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
14.7K
相关概念视频
Sulfate Attack on Concrete
883
Sulfate attack on concrete is a deterioration process characterized by a whitish discoloration beginning at the edges and corners, accompanied by cracking and spalling. This phenomenon occurs when sulfates react with the components of hardened concrete, forming compounds like calcium sulfate and calcium sulfoaluminate which occupy more space than the substances they replace, causing the concrete to expand and disrupt.
Sulfates from sources like soil, groundwater, or industrial effluents...
Sulfates from sources like soil, groundwater, or industrial effluents...
883
Alkali Aggregate Reaction in Concrete
686
The alkali-aggregate reaction in concrete involves natural siliceous minerals in aggregates reacting with alkaline hydroxides derived from cement alkalis. This reaction forms an alkali-silica gel that absorbs water, swells, and increases in volume, which is confined by the surrounding cement paste, creating internal pressures that crack and disrupt the concrete. The extent of expansion and damage can be partly attributed to the alkali-silica reaction's osmotic hydraulic pressure and the...
686
Pozzolans
677
Pozzolans are siliceous or aluminous materials blended with Portland cement. They interact with the calcium hydroxide produced during the hydration of Portland cement and contribute to improved strength and durability of concrete. The pozzolanic activity, a measure of a pozzolan's effectiveness, is typically assessed using the strength activity index, as defined in ASTM C 618-93, which calculates the ratio of the compressive strength of cement mixtures with and without pozzolan.
Fly ash is...
Fly ash is...
677
Acid Attack on Concrete
922
When acids come into contact with concrete, they initiate a chemical reaction that dissolves the hydrated cement paste. This process leads to softening and structural weakening of the concrete. This issue is commonly observed in environments such as chimneys, sewers, and industrial settings. The severity of the damage increases as the pH of the water interacting with the concrete drops below 6.5. In particular, a pH under 4.5 can cause significant concrete damage.
The rate at which hydrogen...
The rate at which hydrogen...
922
