分散剂对土状石墨在水中润湿分散性的影响

Effect of Dispersants on Dispersity and Wettability of Amorphous Graphite

为筛选出能提高土状石墨在水中润湿、分散性的药剂,采用搅拌法改性,以分散率、接触角为评价指标,研究了无机电解质、阴离子表面活性剂单独及复合作用对石墨在悬浮液体系中分散稳定性和润湿性的影响,并借助红外光谱分析了改性机理。分散剂单独作用结果表明:四硼酸钠(Na2B4O7)、十二烷基苯磺酸钠(SDBS)对土状石墨基本无分散、润湿作用;羧甲基纤维素钠(CMC)、木质素磺酸钠对土状石墨分散润湿效果显著;萘磺酸盐(NNO)能显著改善土状石墨的分散性,但对其润湿性能基本无影响。分散剂复合使用研究表明,复配能够提高土状石墨在水中的分散性,CMC-Na2B4O7复合分散效果最好,二者用量分别为土状石墨质量的0.5%和2.5%时,土状石墨分散率为95.55%,润湿接触角为76.37°。

The influence of inorganic electrolyte and anionic surfactant and their coupled composites on dispersity and wettability of amorphous graphite were studied with stirring method. The effects were measured by scatter coefficient and wetting contact angle. Modification characteristics were analyzed with infrared absorption spectra. Single dispersant experiments show that Na2B4O7 and sodium dodecyl benzene sulfonate （SDBS） have little effect on dispersity and wettability of amorphous graphite, while sodium carboxy methyl cellulose （CMC） and sodium lignin sulfonate are good modifiers to them, in addition, aphthalene sulfonate （NNO） is good dispersant to amorphous graphite but not effective modifier to its wettability. The modification effects of composite dispersants to amorphous graphite show that composite dispersants work more effectively than single dispersants. Composite dispersant that constitutes of CMC and Na2B4O7 can achieve the best modification effect. When mass ratio of CMC and Na2B4O7. 10H2O to amorphous graphite are 0.5% and 2.5%, the dispersity and wettability of graphite suspension system reach 95.55% and 76.37°, respectively.