| In order to control scale and corrosion problem in industrial cooling water systems for the purpose of efficient and equipments turning normally in a long time, water treatment agents (such as scale and corrosion inhibitor) was usually added to circulating water. With the enhancement of the environmental consciousness, the research of water treatment agent which is non-toxic, pollution-free has become an important research aspect. In comparison with traditional water treatment agent, non-phosphorous water treatment agent derived from capped polyether, easily prepared with lower cost, also have superior corrosive and scale inhibitive and dispersive performances. The main research contents are exhibited as follows:(1) APEM macromonomers possess the properties of electrolytes, and their chemical stability was also improved by displacing hydrogen of hydroxyl group in the structure of allylpolyethylene monoether (APEGn). APEG and APEM were characterized systemically by Fourier transform infrared spectroscopy (FT-IR),1H Nuclear magnetic resonance (1H-NMR),13C Nuclear magnetic resonance (13C-NMR) and bromine value. Bromine value analysis indicate that C=C double bonds were not destroyed during the process of carboxy methylation reaction. A series of copolymers as water treatment agent were prepared through free radical polymeric reaction in aqueous solution by using of AA as small molecule monomers and APEM (AMPS) as macromonomers.(2) The best synthesis process is as following:monomer ratio AA:APEM=2:1,2% initiator amount, drop time for 1.0h, reaction temperature at 80℃ and reaction time for 2h. The inhibition ratio for CaCO3 is 80% at the dosage of 8 mg·L-1, while the inhibition ratio for CaSO4 and Ca3(PO4)2are 95% at dosage of 4 mg·L-1 and 100% at 5 mg·L-1. The crystals of CaCO3, Ca3(PO4)2 and CaSO4 in the absence and presence of APEM/AA were extensively characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The shape and crystal dismension take great change upon the addition of APEM/AA, so the same as the crystal form.(3) It is shown APEM/AA has excellent dispersancy activity towards Fe2O3, about 22% light transmittance when the dosage is 6 mg·L-1 under the conditions of 150 mg·L-1 Ca2+,10 mg·L-1 Fe2+, T=50℃, t=6.0 h. APEM/AA is also a good cathode corrosion inhibitor, which gain 70% inhibition at threshold dosage of 60 mg·L-1.(4) APEM/AA/APTA exhibited 70% calcium carbonate inhibition at a level of 9 mg·L-1,90% calcium sulfate inhibition at threshold dosage of 6 mg·L-1. APEM/AA/APTA displayed better ability to control scale deposition than common nonphosphorus inhibitors in solutions. The linear relationship between APEM/AA/APTA fluorescent intensity and its dosage is good. The correlation coefficient (r) is 0.99672 and detection limit of APEM/AA/APTA is 0.38 mg·L-1. The fluorescent performance of the copolymer was evaluated. The effects of pH, temperature, the other water treat agent on the fluorescent intensity were surveyed.(5) The best synthesis process is as following:monomer ratio AA:AMPS:APEM=4:05:0.5,6% initiator amount, drop time for 1.5h, reaction temperature at 80℃ and reaction time for 3h. The inhibition ratio for CaCO3 is 75% at the dosage of 8 mg·L-1, while the inhibition ratio for CaSO4 and Ca3(PO4)2 are 95% at dosage of 5 mg·L-1 and 85% at 3 mg·L-1. APEM/AMPS/AA has excellent dispersancy activity towards Fe2O3, about 20% light transmittance when the dosage is 9 mg·L-1 under the conditions of 150 mg·L-1 Ca2+,10 mg·L=1 Fe2+, T=50℃, t=6.0 h. Compare to APEM/AA, APEM/AA/APTA exhibited 75% barium sulfate inhibition at a level of 16 mg·L-1. The crystals of CaCO3, Ca3(PO4)2, BaSO4 and CaSO4 in the absence and presence of APEM/AMPS/AA were extensively characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The shape and crystal dimension take great change upon the addition of APEM/AMPS/AA, so the same as the crystal form. |
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