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11.
提出了用膜电解法处理低浓度SO2吸收液的方法,介绍了三室电解槽的设计原理及在电场作用下,电解槽内离子的迁移和电解反应机理,系统地讨论了电解槽组成单元材料(如阳离子交换器)的选择及在H2SO4-NaHSO3-Na2SO3体系中金属阳极的选择等,并进行了试验验证,得到了很好的结果。 相似文献
12.
Ricardo Beristain‐Cardoso Anne‐Claire Texier Reyes Sierra‐Álvarez Jim A Field Elías Razo‐Flores Jorge Gómez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1197-1203
BACKGROUND: Simultaneous removal of sulfur, nitrogen and carbon compounds from wastewaters is a commercially important biological process. The objective was to evaluate the influence of the CH3COO?/NO3? molar ratio on the sulfide oxidation process using an inverse fluidized bed reactor (IFBR). RESULTS: Three molar ratios of CH3COO?/NO3? (0.85, 0.72 and 0.62) with a constant S2?/NO3? molar ratio of 0.13 were evaluated. At a CH3COO?/NO3? molar ratio of 0.85, the nitrate, acetate and sulfide removal efficiencies were approximately 100%. The N2 yield (g N2 g?1 NO3?‐N consumed) was 0.81. Acetate was mineralized, resulting in a yield of 0.65 g inorganic‐C g?1 CH3COO?‐C consumed. Sulfide was partially oxidized to S0, and 71% of the S2? consumed was recovered as elemental sulfur by a settler installed in the IFBR. At a CH3COO?/NO3? molar ratio of 0.72, the efficiencies of nitrate, acetate and sulfide consumption were of 100%, with N2 and inorganic‐C yields of 0.84 and 0.69, respectively. The sulfide was recovered as sulfate instead of S0, with a yield of 0.92 g SO42?‐S g?1 S2? consumed. CONCLUSIONS: The CH3COO?/NO3? molar ratio was shown to be an important parameter that can be used to control the fate of sulfide oxidation to either S0 or sulfate. In this study, the potential of denitrification for the simultaneous removal of organic matter, sulfide and nitrate from wastewaters was demonstrated, obtaining CO2, S0 and N2 as the major end products. Copyright © 2008 Society of Chemical Industry 相似文献
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M. J. Vissenberg P. W. de Bont E. M. van Oers R. A. de Haan E. Boellaard A. M. van der Kraan V. H. J. de Beer R. A. van Santen 《Catalysis Letters》1996,40(1-2):25-29
Ion exchanged CoNaY was sulfided at 473 and 673 K and subsequently heated in He at 673 and 773 K. The resulting samples were characterized by means of overall sulfur analysis, temperature programmed Ar treatment and Fourier transform infrared spectroscopy. It was shown that during He flushing at sufficiently high temperature a protolysis reaction occurs resulting in the decomposition of Co sulfide into Co2+ ions and H2S. 相似文献
16.
微波消解-ICP-AES法测定菜油中P、S 总被引:2,自引:0,他引:2
采用微波加热,在高温高压下酸消解样品,运用电感耦合等离子体原子发射光谱法(ICP-AES)同时测定菜油中P、S。本法选用紫外区谱线P178.221nm、S180.669nm,避免了基体中存在的Fe、Zn、Al、Cu、Mn、Ca等元素的光谱干扰。实验通过用纯氮吹扫光谱仪光路的方法消减空气中氧对紫外线的吸收,获得了足够的灵敏度。该方法简便、快速,稳定可靠,P、S检出限分别为0.067、0.078μg/ml,RSD为1.35%~5.05%,回收率为89.0%~100.9%。 相似文献
17.
D. Bojinova R. Velkova Iv. Grancharov St. Zhelev 《Nutrient Cycling in Agroecosystems》1996,47(3):227-232
It is well known that the production of phosphoric fertilizers by traditional methods is connected with certain environmental problems, particularly related to use of acids during the decomposition of natural phosphates. A basic problem is also the fact that only 15 – 20% of the phosphorus contained in superphosphates is assimilated by plants.The development of methods to process natural phosphates without acid precipitation has potential advantages and in this respect biotechnological processing of natural phosphates in order to obtain organo-mineral fertilizers is very promising. The possibility of bioconverting the phosphorus of natural phosphates by usingAspergillus niger fungi through their deep incubation has been investigated. The investigations aim to achieve a high degree of P2O5 extraction from the phosphates with conversion from a non-utilizable to a utilizable form. The influence of the fungal strain, the kind of nutritive medium and the time of incubation of the process of biological mobilization of the phosphate rock is examined.It was established that the time of incubation, the kind of micro-organisms of theAspergillus niger group, as well as the kind of nutritive medium, influence significantly the process of bioconversion and the conversion of phosphorus from non-utilizable to water-soluble and utilizable for plants form. A maximum degree 90% of phosphorus extraction in the form of water-soluble and citrate-soluble has been reached for 10-day incubation. Physicochemical examinations have been carried out and they have proved that, as a result of the produced organic acids, a process of decomposition of the initial Tunisian phosphorite takes place. 相似文献
18.
本文采用正交设计及方差分析法,确定了 SO_3磺化法合成 PNTS 新工艺的最佳工艺条件;并从技术及经济方面将新工艺同国内现有的生产老工艺进行了分析对比。 相似文献
19.
常减压蒸饱装置几起典型硫腐蚀事例分析 总被引:1,自引:1,他引:0
随着高(含)硫原油加工量的增加,硫腐蚀事故也时有发生。通过对常减压装置硫腐蚀事例进行分析,指出合理的混炼比,加强“一脱三注”管理,材料升级和实施腐蚀监测是防止腐蚀事故发生的有效措施。 相似文献
20.
罐车内壁元素硫的来源机理 总被引:2,自引:1,他引:1
分析了罐车装运喷气燃料中元素硫的来源途径,探讨了罐车内壁元素硫的来源机理。理论分析和实验研究结果表明,罐车内壁元素硫主要来源于硫腐蚀,罐车内存在金属硫化物、水分、氧气等条件时可促进元素硫的生成;沉积于罐壁腐蚀内层的元素硫难以清洗除去,却可慢慢溶解于油品中而致使喷气燃料银片腐蚀不合格。采用汞滴法可快速有效地测定罐车残油中的元素硫含量,检测不合格的罐车不用于装运喷气燃料,可有效地解决喷气燃料银片腐蚀不合格的生产问题。 相似文献