A biocompatible diatomite-based material with yeast implantation for dye adsorption

Abstract

Biosorption has exhibited promising progress in dye effluent treatment because of ecologically sustainability, and yeast is considered as a representative biosorbent due to its inherent adsorption capability and ready availability. To promote the adsorption and avoid secondary pollution, a biocompatible and tough matrix material should be used for supporting soft yeasts. A novel biocompatible material was therefore synthesized hydrothermally by natural diatomite originated from algae (diatoms). With reinforced phases of C–S–H, tobermorite or analcime formed in the diatomite-based matrix, the flexural strength reached up to more than 20 MPa, and further the porosity and cation exchange capability were also promoted. Due to the biocompatible diatomite-based materials, yeast was implanted within the matrix readily and thus promoted the adsorption greatly. Comparative experiments for methylene blue (MB) adsorption showed that with yeast implantation much more MB could be adsorbed or removed than that without yeast implantation, and the maximum MB incremental adsorption was even close to MB adsorption for neat yeast, suggesting that the diatomite-based matrix could offer the almost maximum absorbability for yeast due to the biocompatible environment for yeast. The maximum MB adsorption of 93.3 mg g−1 was obtained in this work in agreement with results from the Langmuir model, indicating a competitive alternative composite biosorbent for MB dye removal.