Preparation and Characterization of Copper Borates as Lubricant Additives

• Published in: Journal of materials science and engineering. B 2014-04, Vol.4 (4), p.95-108
• Main Author: Burcu Alp Sevdiye Atakul Savrik Devrim Balkose
• Format: Article
• Language: English
• Subjects: X射线衍射仪; 制备方法; 润滑油添加剂; 混合时间; 硝酸根离子; 硼酸盐; 表征; 酸铜
• ISSN: 2161-6221; 2161-6221
• DOI: 10.17265/2161-6221/2014.04.004

The present study attempts the preparation of copper borate as a lubricating oil additive by the reaction of copper nitrate and borax solutions. Effects of borax/copper ratio, surface active agent （Span 60）, pH, temperature and mixing time on properties of the products were investigated. The obtained products were not pure form; therefore they were analyzed in detail. They were characterized by color measurement, X-ray diffraction, SEM, zeta sizer, ICP, EDX, TG, DSC, CHNS analysis and FTIR spectroscopy. Mainly Cu2（OH）3NO3 with nitrate ions partially substituted with borate ions was obtained at pH 3.7. There were borate ions equivalent to 0.32 tools of Cu（BO）2 per tool of CUE（OH）3NO3. The borate ions should have replaced partially the nitrate ions in Cu2（OH）3NO3 without changing its crystal structure. On the other hand, Cu （BO2）l 5（OH）074＇（H20）015 was produced at pH 10.2. It also contained 0.11 mol NO3- per tool. By mixing of dilute solutions at pH 8.2 and drying at room temperature nanopartieles of Cu（BO2）I 5（H20）6 having 0.05 NO3 per tool was obtained. The precipitates obtained at pH 10.1 and 8.2 were tested as lubricant additives. When they were added to lubricating oil with Span 60, the friction coefficient was reduced 28 % and 65 % for the precipitates prepared at pH 10.1 and 8.2, respectively.