为揭示EDTA对硅酸聚合沉淀过程的影响机理,本文结合浊度分析法和粒度分析法研究了有无添加EDTA的不同浓度硅酸钠溶液的浊度变化及粒径变化.浊度分析结果发现,硅酸钠浓度为400 mg·L-1和800 mg·L-1时,溶液的浊度基本相同,在3 NTU左右.而硅酸钠浓度大于800 mg·L-1时,溶液浊度随浓度的增大而增大.在同样的硅酸钠溶液中添加一定浓度的EDTA时,混合溶液的浊度大于相应的硅酸钠溶液的浊度,且添加的EDTA浓度越大浊度越大,说明EDTA促进硅酸的聚合反应.粒度分析结果发现,添加EDTA的混合溶液中所形成的硅胶颗粒的粒径比相应的硅酸钠溶液的粒径大,且随EDTA浓度的增加而增大,说明EDTA促进硅胶颗粒的生长.根据FT-IR分析结果推测EDTA对硅酸聚合沉淀的促进机理如下:EDTA分子内所含的羰基上的氧原子或胺基上的氮原子通过氢键与溶液中已形成的硅胶体表面的Si-OH官能团相互作用,通过P-P反应把小的硅胶颗粒集聚到一起,促进硅胶颗粒的生长,从而促进硅酸的聚合沉淀反应.
参考文献
[1] | Nishida, I.;Shimada, Y.;Saito, T.;Okaue, Y.;Yokoyama, T..Effect of aluminum on the deposition of silica scales in cooling water systems[J].Journal of Colloid and Interface Science,20091(1):18-23. |
[2] | 李广兵;方健;徐敬;李杰.水垢成垢诱导期机理研究[J].同济大学学报(自然科学版),2000(5):555-559. |
[3] | 罗艳归;隋贤栋;黄肖容.水垢防治技术研究进展[J].工业水处理,2012(1):18-20. |
[4] | Antonia Ketsetzi;Aggeliki Stathoulopoulou;Konstantinos D.Demadis.Being "green" in chemical water treatment technologies:issues,challenges and developments[J].Desalination: The International Journal on the Science and Technology of Desalting and Water Purification,20081/3(1/3):487-493. |
[5] | 周本省.循环冷却水系统中的水垢及其控制[J].腐蚀与防护,2006(01):26-31,37. |
[6] | 蒋伟;徐军;翟军.管道中水垢的形成机理及清洗方法分析[J].清洗世界,2008(12):19-25. |
[7] | Shuqin Bai;Yutaka Tsuji;Yoshihiro Okaue.First Detection of a Silicic Acid Complex with a Catechol Derivative under Natural Conditions[J].Chemistry Letters,200811(11):1168-1169. |
[8] | 孙立新;田民格;李爱兵.供热机组新建锅炉EDTA二钠清洗[J].清洗世界,2012(11):18-21. |
[9] | 陈泽峰.锅炉EDTA化学清洗[J].清洗世界,2007(02):15-18. |
[10] | Bai, S.;Naren, G.;Noma, H.;Etou, M.;Ohashi, H.;Fujino, Y.;Doi, K.;Okaue, Y.;Yokoyama, T..Silica deposition induced by isolated aluminum ions bound on chelate resin as a model compound of the surface of microbes[J].Colloids and Surfaces, B. Biointerfaces,2012:208-213. |
[11] | Dominique J. Tobler;Sam Shaw;Liane G. Benning.Quantification of initial steps of nucleation and growth of silica nanoparticles: An in-situ SAXS and DLS study[J].Geochimica et Cosmochimica Acta: Journal of the Geochemical Society and the Meteoritical Society,200918(18):5377-5393. |
[12] | Al-Oweini, R;Ei-Rassy, H.Synthesis and characterization by FTIR spectroscopy of silica aerogels prepared using several Si(OR)(4) and R '' Si(OR ')(3) precursors[J].Journal of Molecular Structure,20091/3(1/3):140-145. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%