最初的自由氨对于强大的酸性部分化在批量反应堆测序过程中至关重要
Siqi Li1, Xiaofeng Kang1, Jiang Men2
1State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China.
Water research
|March 4, 2025
概括
在低氨水下,在废水处理中实现稳定的部分化 (PN) 是一个挑战. 这项研究确定了自由氨和pH值作为在测序批量反应堆 (SBR) 中强大的PN的关键因素.
科学领域:
- 环境工程 环境工程
- 废水处理 废水处理
- 微生物生态学 微生物生态学
背景情况:
- 部分化 (PN) 的实施受到低入 (NH4+-N) 度的阻碍.
- 在处理低强度废水的测序批量反应器 (SBR) 中,酸盐氧化细菌 (NOB) 的稳定性和抑制边界条件尚不清楚.
- 在SBR中的动态环境因素使得实现稳定的PN变得复杂.
研究的目的:
- 在SBR中确定稳定部分化 (PN) 的关键因素.
- 在动态环境条件下扩展稳定PN的边界条件.
- 研究SBR中自由氨 (FA) 和自由酸对NOB的联合抑制.
主要方法:
- 长期运行 (580天) 的常规配置的SBR.
- 对不同NOB的动态自由氨 (FA) 和自由酸对不同NOB的联合抑制的研究.
- 运动参数测量和模型开发,用于预测PN条件.
主要成果:
- 在低性条件下,初始自由氨 (FA) 度对于确定PN至关重要.
- 尼托斯皮拉NOB对FA抑制高度敏感 (KI_FA=0.35毫克NH3-N/L),降低了所需的FA水平.
- 将pH值降至5.4有效抑制了不耐酸的Ca. 尼托托加NOB,对于维持PN至关重要.
结论:
- 最初的FA度是SBR中实现稳定和强大的酸性部分化 (PN) 的关键因素.
- 控制FA和pH可有效抑制NOB,使低强度废水中的PN稳定.
- 研究结果为在传统的SBR中强大的酸性PN实施提供了指导.
相关概念视频
Preparation of Amines: Alkylation of Ammonia and Amines
3.2K
Alkylation is one of the methods used to prepare amines. Direct alkylation of ammonia or a primary amine with an alkyl halide gives polyalkylated amines along with a quaternary ammonium salt through successive SN2 reactions. This process of making the quaternary salt through the direct alkylation method is called exhaustive alkylation.
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
3.2K
Titration of a Weak Base with a Strong Acid
4.5K
The titration curve of a weak base like ammonia with a strong acid like hydrochloric acid is the mirror image of the titration curve of a weak acid with a strong base.
Using the ICE table and substituting the Kb value, we calculate the initial pH of 50 mL of 0.1 M ammonia to be 11.11. Addition of 25 mL of 0.1 M hydrochloric acid to this solution of ammonia results in a buffer with an equal concentration of ammonia and ammonium ions. The pH of this buffer can be calculated by substituting these...
Using the ICE table and substituting the Kb value, we calculate the initial pH of 50 mL of 0.1 M ammonia to be 11.11. Addition of 25 mL of 0.1 M hydrochloric acid to this solution of ammonia results in a buffer with an equal concentration of ammonia and ammonium ions. The pH of this buffer can be calculated by substituting these...
4.5K
2° Amines to N-Nitrosamines: Reaction with NaNO2
4.0K
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
4.0K
Overview of Nitrogen Metabolism
7.8K
Nitrogen is a very important element for life because it is a major constituent of proteins and nucleic acids. It is a macronutrient, and in nature, it is recycled from organic compounds and stored in the form of ammonia, ammonium ions, nitrate, nitrite, or nitrogen gas by many metabolic processes. Many of these metabolic processes are carried out only by prokaryotes.
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...
7.8K
Basicity of Aliphatic Amines
5.6K
Amines can behave as Brønsted–Lowry bases by accepting a proton from the acid to form corresponding conjugate acids. Due to a lone pair of nonbonding electrons, aliphatic amines can also act as Lewis bases by forming a covalent bond with an electrophile.
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates...
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates...
5.6K
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
3.2K
Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
3.2K


