Synthesis and evaluation of a novel dispersant with jellyfish-like 3D structure for preparing coal–water slury

Abstract

TAA, a new dispersant for making coal–water slurry (CWS), has been synthesized by grafting copolymerization of oxidized tannic acid (TA) and acrylic acid (AA). 1H NMR and FTIR tests revealed that TAA has a unique jellyfish-like 3D molecular structure, in agreement with experimental evidences from contact angle and zeta potential measurements. The surfactivity of TAA in aqueous solution was characterized using a surface-tension meter. The rheological properties and static stability of CWS containing 66wt.% coal with 0.3wt.% TAA dosage were examined and compared with slurries prepared with two commercial dispersants, i.e. sodium dodecyl sulfate (SDS) and sodium polystyrene sulfonate (PSS). TAA showed excellent slurry-making performance due to its special 3D structure, with polar and non-polar sites in the bottom plane exhibiting affinity to those on the coal particle surfaces to build strong interactions. CWS prepared with TAA showed good stability and favorable rheological properties compared with slurries prepared with SDS and PSS. The present work provides a new approach to the development of high-performance and environmentally friendly S/N-free dispersants from renewable resources.