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1.
本文对IDR尿素装置的目前生产情况进行了统计和分析。同时根据观察、统计和测试,对某些问题提出思路。 相似文献
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The dissolution mechanism of hemimorphite in NH3-(NH4)2SO4-H2O system at 298.15 K was investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis. The results show that hemimorphite is soluble in NH3-(NH4)2SO4-H2O system and its residue exists in the form of an amorphous SiO2 layer on the hemimorphite surface. The XPS data also indicate that the Si 2p3/2 and O ls spectra of the hemimorphite are broadened and shift to higher binding energies and their binding energies are closer to silica with an increase of total ammonia and time. Solubility of hemimorphite in NH3-(NH4)2SO4-H2O system was measured by means of isothermal solution method at 298.15 K based on the study of the dissolution mechanism of hemimorphite. The results show that the solubility of zinc in solution increases firstly and then decreases with the increase of cr(NH3) (total ammonia concentration) at different NH3/NH4^+ ratios. The solubility of silicon in solution decreases from 0.0334 mol/kg in ct(NH3)-4.1245 mol/kg NH3-(NH4)2SO4-H2O solution to 0.0046 mol/kg in cT(NH3)=7.6035 mol/kg NH3-(NH4)2SO4-H2O solution. 相似文献
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结合作者的量热测定结果和前人的工作,研究了氧化铝工业中最常见的几种铝化合物如α-Al2O3,γ-Al2O3,三水铝石一水软铝石和一水硬铝石的基本热力学性质:标准生成焓、标准熵、标准生成Gibbs自由能和热容,得到了可靠,自洽的结果。 相似文献
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Effect of 20kHz ultrasound on alumina hydrate precipitation from seeded sodium aluminate solution 总被引:2,自引:0,他引:2
1 INTRODUCTIONInthealuminaindustry,precipitationofaluminahydrateintheBayerprocessisaveryimportantopera tion .Innumerousinstanceswh 相似文献
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1 INTRODUCTIONMechanicalactivationiswidelyappliedinen hancingmetallurgicalprocess[1~ 3] andchemicalsyn thesis[4 ,5] .Sofaritisdifficultt 相似文献
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A new type of thermal stabilizer, antimony pent (isooctyl thioglycollate) (Sb(SCH2 COOC8 H17 )5), was synthesized by using antimony trioxide, isooctanol and thioglycolic acid in 2 steps. Firstly, antimony trioxide was oxidized into colloidal antimony peroxide. Then antimony peroxide and isooctyl thioglycollate reacted stoichiometrically for 2 h with the yield of 87%. This compound was used as thermal stabilizer for polyvinyl chloride(PVC).The results show that the thermal stability time is 52 rain at 200℃ by heat-ageing oven test when adding 2. 5% thermal stabilizer to PVC resin. Compared with antimony tris(isooctyl thiolycollate), the initial thermal stability of antimony pent(isooctyl thioglycollate) is better than that of antimony tris(isooctyl thioglycollate), while the longterm thermal stability time is shorter than that of antimony tris(isooctyl thioglycollate). Meanwhile, the synergism of antimony pent(isooctyl thioglycollate) with calcium stearate was studied, indicating that when the mass ratio of antimony pent(isooctyl thioglycollate) to calcium stearate is 2:1, the thermal stability time of PVC is 58 min. 相似文献
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