A novel phosphorous-free terpolymer, used as a decalcifying agent for removing calcium from crude oil, was prepared through a free-radical polymerization reaction of acrylic acid (AA), allylpolyethoxy amino carboxylate (APEA), and 2-hydroxyethyl acrylate (HEA) in water with ammonium persulfate as initiator. The structure of the synthesized AA–APEA–HEA terpolymer was characterized by Fourier transform infrared spectrometry and 1H nuclear magnetic resonance (1H-NMR). AA–APEA–HEA was used to remove calcium from Luning pipeline crude oil. The effects of several factors, such as molar ratio, dosage, and reaction temperature on calcium removal efficiencies from crude oil were evaluated. The results indicated that the removal of calcium from crude oil using AA–APEA–HEA was far more efficient than that using AA–APEA, PAA, HPMA, and PESA under the same conditions. The optimum conditions for calcium removal from crude oils were as follows: (a) molar ratio of AA–APEA–HEA, 2 : 1 : 0.5; (b) dosage of AA–APEA–HEA, 100 ppm; (c) reaction temperature, 100 °C. Under these conditions, the removal efficiency of calcium from Luning pipeline crude oils was approximately 98.63%. Furthermore, the proposed decalcification mechanism suggests surface complexation and chelation between the carboxylic (–COO−) and amino (–NH2) functional groups and Ca2+, with the polyethylene glycol segments increasing its solubility in water and the lipophilic ester groups increasing its affinity to oil.
Yan Lv,Juguo Dai,Long Xia,Lili Luo,Yiting Xu,Lizong Dai
To avoid potential ecological and health problems caused by phosphorus-based flame retardants, a novel phosphorus-free PBA-Salen-Ni flame retardant is successfully synthesized in this work. In a nutshell, boron-containing metal complexes are prepared by nickel salts and chelating PBA-Salen molecule (PBA: p -phenylenediboronic acid). While the obtained material inherently has good compatibility and can endow polymers with good flame retardant properties at low addition levels. Besides, the char shielding layer and the “labyrinth effect” of the special porous char layer structure formed after the combustion of EP/PBA-Salen-Ni retard the transfer of volatile products, giving EP excellent smoke suppression properties. The results show that the limiting oxygen index value of the EP/PBA-Salen-Ni composites is increased from 25.6% (pure EP) to 30.5%, and it can pass the UL-94 V-0 rating when the addition amount is only 5wt%. Particularly, compared with pure EP, the total smoke production (19.9 m 2 ) and peak heat release rate (859.6 kW m −2 ) of EP/PBA-Salen-Ni composites are reduced by 36% and 33%, respectively. Therefore, this work provides a new idea for the rational design of phosphorus-free flame retardants that are mainly on condensed phase flame retardancy and have a good smoke suppression effect.
危险品化学品经营许可证（带存储）