Anti-Agglomerator of Tetra-n-Butyl Ammonium Bromide Hydrate and Its Effect on Hydrate-Based CO2 Capture

Tetra-n-butyl ammonium bromide (TBAB) was widely used in the research fields of cold storage and CO2hydrate separation due to its high phase change latent heat and thermodynamic promotion for hydrate formation. Agglomeration always occurred in the process of TBAB hydrate generation, which led to the blockage in the pipeline and the separation apparatus. In this work, we screened out a kind of anti-agglomerant that can effectively solve the problem of TBAB hydrate agglomeration. The anti-agglomerant (AA) is composed of 90% cocamidopropyl dimethylamine and 10% glycerol, which can keep TBAB hydrate of 19.3–29.0 wt. % in a stable state of slurry over 72 h. The microscopic observation of the morphology of the TBAB hydrate particles showed that the addition of AA can greatly reduce the size of the TBAB hydrate particles. CO2gas separation experiments found that the addition of AA led to great improvement on gas storage capacity, CO2split fraction and separation factor, due to the increasing of contact area between gas phase and hydrate particles. The CO2split fraction and separation factor with AA addition reached up to 70.3% and 42.8%, respectively.Keywords:CO2separation;TBAB;IGCC;anti-agglomerant;micromorphology;hydrate