A comparative dynamic study of seawater pretreatment using experimental and pilot bubble tower.

In the previous study, greenhouse gas CO2 was successfully used as the precipitator to realize its carbonation by calcium ions in seawater with the help of magnesium oxide. In this study, the reaction process was firstly analyzed by a proposed reaction mechanism, and then the dynamic simulation of the gas-liquid-solid system was carried out via kinetic Monte Carlo simulation. Based on the reaction mechanism, the continuous experimental study was realized in a bubble column. The effects of air flow rate, carbon dioxide flow rate and temperature on the effectiveness evaluation indexes of decalcification efficiency, total mass transfer coefficient and carbon sequestration rate were studied. Finally, a bonnet tower with a diameter of 1 m and a height of 8 m was built to carry out the pilot test. In the laboratory experiments, the calcium removal rate reached 94%, the carbon sequestration rate reached 63.6%, and pure micron calcium carbonate products were obtained. The decalcification rate reached 95% in the pilot test, which is consistent with the results of the laboratory experiment.

[Preparation of biporous polymeric microspheres coupled with mercaptopyridine and its application in rapid purification of plasmid DNA].

Plasmid is a kind of popular nonviral vector in gene therapy. To produce large quantities of plasmid, an efficient large-scale purification process needs to be developed. In general, liquid chromatography is the most important tool for the analytical and preparative separation of plasmid DNA. In this study, biporous polymeric microspheres coupled with mercaptopyridine were synthesized for the purification of plasmid DNA. From the results of experiments, it can be inferred that the mechanism for the purification of the plasmid DNA with MP-BiPR is based on the hydrophobic interaction. When the load was 10 mL with the content of plasmid of 0.30 mg/mL and the content of RNA of 0.44 mg/mL, a flow rate was set up to 4 mL/min (20 cm/min). The separation was finished in 10 min, and the plasmid was completely recovered with undetectable impurities of nucleic acids and proteins. The load of the column for RNA was up to 2.2 mg/mL.