摘要：

过氧化镁作为释氧化合物，具有活性氧含量高、与水反应生成的氢氧化物碱性弱、对环境影响小等优点，在环境修复方面有非常大的应用前景。但现有过氧化镁制备技术存在工序复杂、产品纯度低等问题，极大地制约了其应用与推广。以氧化镁和过氧化氢为原料制备了高纯度过氧化镁，用表面活性剂进行改性以增强其在含水层中的迁移能力，并用于原位修复。实验结果表明：氧化镁质量（以g计）与过氧化氢体积（以mL计）之比为1∶16时，制备的过氧化镁纯度可达94%，继续增加过氧化氢的用量不会显著提高过氧化镁的纯度。表面活性剂可提高过氧化镁悬浊液的稳定性，其中十二烷基硫酸钠和羧甲基纤维素钠的复配表面活性剂对过氧化镁的改性效果显著。2种表面活性剂用量均为过氧化镁质量的2%时改性效果最佳，静置1 h不分层沉淀。改性后的过氧化镁在含水层介质中具备较强的迁移能力，且较大的介质粒径和较高的流速有利于过氧化镁的迁移。

关键词: 过氧化镁, 缓释, 生物修复, 迁移性能

Abstract:

As an oxygen releasing compound, magnesium peroxide has high content of reactive oxygen species, weak alkalinity of hydroxide generated by reaction with water, and little impact on environment. Therefore, magnesium peroxide has great application prospects in environmental remediation. However, the existing magnesium peroxide preparation technology has a series of problems, such as complex preparation process, low product purity, which greatly restricts its application and promotion. High-purity magnesium peroxide was prepared from magnesium oxide and hydrogen peroxide, and modified with surfactants to enhance its migrational ability in aquifers, and applied for in-situ remediation. Experimental results showed that the purity of magnesium peroxide reached 94% when the ratio of magnesium oxide mass(in grams) to hydrogen peroxide volume(in mL) was 1∶16, and continuing to increase the amount of hydrogen peroxide would not significantly improve the purity of magnesium peroxide. Surfactant could improve the stability of magnesium peroxide suspension, in which the combination surfactant of sodium dodecyl sulfate and sodium carboxymethyl cellulose had a significant effect on the modification. The modification effect was best when the dosage of both surfactants was 2% of the mass of magnesium peroxide, without separation and sedimentation in 1 hour. The modified magnesium peroxide has excellent migrational ability in aquifer media, and the larger medium particle size and higher flow rate are beneficial to the migration of magnesium peroxide.

Key words: magnesium peroxide, sustained release, bioremediation, migrational ability

中图分类号: 

• X523