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Available from: Samir I Abu-Eishah,
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    ABSTRACT: The general objective of the present investigation was to make a contribution towards improving the purity of the produced potassium sulfate from (KCl, Arab Potash Company-Dead Sea) and (H2SO4, Jordanian Phosphate Company). The process parameters influencing the contamination of the poisoning chlorine within the product were experimentally investigated. The experiments were performed in a small-scale batch reactor equipped with a high temperature control system. The role of temperature was studied. Higher purity of potassium sulfate was achieved at higher temperatures. The effect of the quality of KCl used was investigated. It was found that implementing fine KCl as reagent is a dvantageous over standard KCl. A completely pure potassium sulfate fertilizer was produced after 110 minutes residence time in the case of using fine KCl.
    American journal of environmental sciences 02/2005; DOI:10.3844/ajessp.2005.139.141 · 1.22 Impact Factor
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    ABSTRACT: Potassium sulfate is used to produce multicomponent fertilizers, free of chlorides. The desalting out of potassium sulfate from an aqueous solution of potassium hydrosulfate was conducted using 40 mass %, 45 mass %, or 50 mass % aqueous solutions of either methanol or propan-2-ol. Composition of the resultant precipitate was analyzed using chemical methods and XRD analysis. The results of the XRD analysis revealed that the main precipitate phase is K2SO4. Small amounts of K5H3(SO4)4 were detected when the desalting out was carried out from 2.5 M KHSO4 solution using 40 mass % and 50 mass % methanol solution. When the amount of potassium bisulfate in the solution increased to 3.5 M and 3.8 M, the main phase consisted of K3H(SO4)2. Generally, the desalting out process using propan-2-ol caused the formation of K3H(SO4)2. Potassium sulfate was obtained only by desalting out the 2.5 M KHSO4 solution using 50 mass % aqueous propan-2-ol.
    Chemical Papers- Slovak Academy of Sciences 02/2008; 62(1):123-126. DOI:10.2478/s11696-007-0088-2 · 1.47 Impact Factor
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    ABSTRACT: Marisma, one of the largest salt-marsh alluvial areas in SW Spain, has been reclaimed since 1970 by artificial drainage and amendment with phosphogypsum (PG) so as to reduce Na+ saturation. Within the reclaimed area, two 250- × 20-m plots were treated as follows: (1) amendment with 25 Mg/ha of PG every 2 to 3 years between 1979 and 2003 (plot PY); (2) like PY but PG treatment stopped after 1997 (plot DR). A contiguous virgin Marisma salt-marsh plot (MV), neither drained nor amended, was the control. In MV, soil microbial biomass C, most enzyme activities and total organic C content were much greater than in PY and DR soils, despite the salinity stress. The decrease in soil organic matter content in PY and DR soils was likely due to cotton-cropping practices, which favoured the organic C mineralisation and nutrients removal by crops. Microbial activity of MV soil, probably stimulated by the rhizodepositions of the natural vegetation, did not suffer from the osmotic effect due to the raising of soil solution ionic strength. Microbial quotient could be ranked as MV > PY > DR, whereas the metabolic quotient had an opposite trend. Thus, both quotients suggested that the interruption of PG amendment was not favouring microbial activity. Principal component analysis clearly identified the chemical and biochemical soil properties mostly affected by the reclamation and also indicated the longer PG amendment in PY plot. Stepwise discriminant analysis identified two physiologically different types of soil microflora, one less active present in the MV virgin soil and another more active present in the reclaimed PY and DR soils.
    Biology and Fertility of Soils 08/2009; 45(7):691-700. DOI:10.1007/s00374-009-0380-0 · 3.40 Impact Factor