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为了促进磷矿伴生氟资源的开发利用,分析归纳了化学加工磷矿石所产生含氟废气的净化和氟回收方法,对利用磷化工副产氟硅酸,进而生产系列无机氟产品的方法和用途作了系统阐述。重点介绍了氟硅酸直接制取无水氟化氢联产氟化铵、白炭黑新工艺,简述了生产方法和工艺流程。由此表明:开发利用磷矿伴生氟资源,既能控制氟污染,又能副产无机氟产品,从而提高磷矿的综合利用效益。 相似文献
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介绍了磷矿伴生氟资源回收利用制无水氟化氢的工艺技术发展,以及国内磷矿伴生氟资源制无水氟化氢的产能及市场需求情况,指出磷矿资源综合利用副产氟硅酸生产氟化氢将是开拓氟资源利用的新途径,制备高纯氢氟酸和无水氟化氢将成为磷肥副产氟硅酸深加工和提高产品附加值的方向之一。 相似文献
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Interchemchina 《精细与专用化学品》2001,9(17):6-8
我国已探明的萤石矿资源总量约占世界总储量的1/3。由于科研、技术、设备等方面相对落后,我国的氟化工还停留在萤石粗加工阶段,相对附加值较高的有机氟衍生物品种单一,大量依赖进口。本文综述了我国含氟精细与专用化学品的生产企业、主要品种、市场供求和科研开发状况,并介绍了日本的部分有机氟产品及其开发与应用情况。日本是有机氟产品深加工的重要基地,市场把握能力和高技术保证了产品的高附加值。 相似文献
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Alexander M. Puziy Olga I. Poddubnaya Alberto Castro-Muñiz Juan M.D. Tascón 《Carbon》2007,45(10):1941-1950
Activated carbons were prepared by phosphoric acid activation of fruit stones in air at temperatures 400-1000 °C. The surface chemistry was investigated by elemental analysis, cation exchange capacity, infrared spectroscopy and potentiometric titration. The porous structure was analyzed from adsorption isotherms (N2 at 77 K and CO2 at 273 K). It was demonstrated that all carbons show considerable cation exchange capacity, the maximum (2.2 mmol g−1) being attained at 700 °C, which coincides with the maximum contents of phosphorus and oxygen. The use of air instead of argon during thermal treatment increased the amount of cation exchangeable surface groups for carbons obtained at 400-700 °C. Proton affinity distributions of all carbons show the presence of three types of surface groups with pK 1.8-3.1 (carboxylic and polyphosphates), 4.8-6.3 (second dissociation of carboxylic, weak acid in polyphosphates and enol structures) and 8.1-9.7 (phenols and enol structures). Carbons obtained in air at 400-600 °C show enhanced copper adsorption from 0.001 mol L−1 Cu(NO3)2 in acidic solutions as compared to carbons obtained in argon. Carbons obtained in air show well-developed porous structure that is equivalent or higher as compared with carbons obtained in argon; the difference being progressively increased with increasing treatment temperature. 相似文献
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多孔粒状陶瓷负载水合氧化锆吸磷材料的制备及其性能研究 总被引:1,自引:0,他引:1
以工业粉状废物为主要原料制备出粒径为2~4 mm,孔隙率为45.93%,表观密度为1.37 g/cm3,单颗抗压强度为47.73 N的粒状陶瓷滤料,并在其上负载水合氧化锆以制备吸磷材料,考察其吸磷性能和影响因素。通过SEM、XRD和FT-IR对材料进行分析,以研究其吸磷机制。结果表明:滤料负载水合氧化锆后,质量增加了20.48%,比表面积由7.15 m2/g增大到19.35 m2/g,大孔结构为主的孔隙结构变为以介孔结构为主。吸磷主要通过其表面的羟基和磷酸根之间的离子交换实现。在30℃、pH为7时,其对磷酸根有较好的吸附能力,饱和吸附量为10.79 mg/g。其吸附等温线符合Langmiur吸附模型,吸附动力学符合二级吸附动力学模型。吸附后的滤料可在NaOH中再生,经多次"吸附-解吸"后,其吸附容量一直稳定在0.5 mg/g左右。 相似文献
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Crop yield and the fate of nitrogen and phosphorus following application of plant material and feces to soil 总被引:1,自引:0,他引:1
Organic materials are the most important sources of nutrients for agricultural production in farming systems of semi-arid West Africa. However, reliance on locally available organic nutrient sources for both crop and livestock production is rapidly becoming unsustainable. A series of feeding and agronomic trials have been conducted to address the role of livestock in sustainable nutrient cycling. This paper reports results of a greenhouse study that evaluated the effects of applying crop residue and browse leaves, or feces derived from these feeds, at equal organic-N application rates (150 kg ha-1), alone or with fertilizer-N (60 kg ha-1), on pearl millet (Pennisetum glaucum [L.] R.Br.) dry matter (DM) yield, nitrogen (N) and phosphorus (P) uptake, on soil nutrients, and on total, labile and recalcitrant fractions of soil organic matter (SOM). Millet DM and cumulative N uptake were most affected by fertilizer-N, followed by plant species and amendment type, although various interactions among these treatments were noted due to variations in the composition of the applied amendments. Fertilizer-N increased total millet DM by 39%, N uptake by 58% and P uptake by 17%, and enhanced N mineralization from most organic amendments, but was applied insufficiently to totally offset N and P immobilization in pots containing leaves of low initial N and P content. Feces alone appeared to supply sufficient N to meet millet-N demands. Nitrogen use efficiency was, in most cases, higher in pots amended with feces than with leaves. Nitrogen in feces apparently mineralized more in synchrony with millet-N demands. Also, the relatively high cell wall content of feces may have provided an effective, temporary sink for fertilizer-N, which upon remineralization provided more N to millet than pots amended with leaves. Whereas most of the P contained in feces mineralized and was taken up by millet, most leaves immobilized P. Assessing the costs and benefits associated with the direct land application of biomass as a soil fertility amendment versus feeding biomass first to livestock then using feces (and urine) to fertilize the soil requires information on both crop and livestock production and associated impacts on nutrient cycling. 相似文献
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