Abstract:

The technology of digital inkjet printing requires inkjet printing dye with high purity and low salt. Based on preparation of GO / nano TiO₂ self-assembled nanofiltration membrane, the size of nano TiO₂ particles and the blending ratio with GO were explored. The optimal GO/TiO₂ composite nanofiltration membrane was obtained in which the TiO₂ particle size was 60 nm and the blending ratio with GO was 1∶1. The pure water permeance was 10.69 L/(m²·h·bar), the rejection of NaCl and Na₂SO₄ was 12.6% and 15.7% respectively, and the rejection of Eriochrome black T, Congo red and Coomassie brilliant blue R were all higher than 99%. The home-made continuous constant volume diafitration device was used to conduct the dye desalination and concentration experiment. The concentration of obtained ink was increased from the initial 2.0 g/L to 9.74 g/L, and the concentration of NaCl and Na₂SO₄ was reduced from the initial 10 g/L to 5.3 mg/L and 11 mg/L respectively, meeting the requirements of digital inkjet printing dye.

Key words: GO/TiO₂ composite membrane, separation, nanoparticles, continuous constant volume diafiltration, nanofiltration

摘要：

数码喷墨打印技术对墨水高纯度和低含盐量要求，不断促使染料纯化技术的开发与研究。基于氧化石墨烯(GO)/纳米二氧化钛(TiO₂)自组装的纳滤膜材料的开发，探究了纳米TiO₂颗粒尺寸和与GO共混比例，所获最优GO/TiO₂复合纳滤膜中TiO₂颗粒尺寸为60 nm，与GO共混比例为1∶1。其纯水通量为10.69 L/(m²·h·bar)，对NaCl和Na₂SO₄的截留分别为12.6%和15.7%，对铬黑T、刚果红和考马斯亮蓝R的截留均高于99%。采用自制的连续恒容渗滤装置对粗品墨水进行染料脱盐浓缩的实验，所获染料的浓度由最初的2.0 g/L浓缩至9.74 g/L，NaCl和Na₂SO₄浓度则由起始10 g/L分别下降至5.3 mg/L和11 mg/L，满足数码印花对墨水高纯度以及低盐度的要求。

关键词: GO/TiO₂复合膜, 分离, 纳米粒子, 连续恒容渗滤, 纳滤