Removal of trace elements from Thar coal to minimize its hazardous effect on the environment
Keywords:
Acid washing; Hazardous effect; Pakistani coal; Thar lignite; Trace elements; X-ray Fluorescence (XRF) SpectrometerAbstract
Four lignite coal samples from Thar coal fields Pakistan were selected for the trace elemental analyses studies. The data was obtained with the use of X-ray Fluorescence (XRF) Spectrometer. It was observed that (Aluminum, Arsenic, Barium, Bromine, Calcium, Cerium, Cobalt, Chromium, Cesium, Copper, Iron, Gallium, Hafnium, Lanthanum, Manganese, Molybdenum, Niobium, Neodymium, Nickel, Lead, Rubidium, Antimony, Scandium, Selenium, Silicon, Tin, Strontium, Samarium, Tantalum, Titanium, Uranium, Vanadium, Tungsten, Ytterbium, Zink and Zirconium) elements were present in all the coal samples under investigation. These trace metals are found to have an adverse effect on the health of the living organisms intact with coal utilization. Some of these elements such as Arsenic, Barium, Beryllium, Chromium, Cobalt, Copper, Lead, Molybdenum, Nickel, Selenium, Uranium, Vanadium and Zinc are extremely harmful to human health, if released to the environment during coal combustion. Therefore, the coal samples were being demineralized with washing the coal samples with standard solution of 2N HCl. The demineralized coal samples were then subjected in the same way to (XRF) Spectrometer for elemental analyses. The elements identified in raw samples were compared with the elements identified in the respective demineralized samples. It was found that demineralization caused better effect, in terms of metals removal from coal.
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