This manuscript pointed out an error on pseudo-second-order rate equation. The mistake in the model was duplicated in number of papers in recent years. This type of error could be avoided if authors have had paid more attentions to details about the model from the original paper. In addition, it may leads to trouble for the reader to locate the original articles. It is very provoking and time-consuming to search for a reference when the information is not correct. This comment offered information for citing original idea of the pseudo-second order kinetic expression. Please consider for its publication. If there are problems, please do not hesitate to contact me. With best regards.