Chemical removal of lead - 5500 Words

Chemical removal of lead (Research Paper Sample) Content: Griffith School of Engineering 7404ENG Advanced Water Wastewater Engg. Assignment à ¢Ã¢â€š ¬Ã¢â‚¬Å" *****   Remediation Methods for Lead Course Convener: **** Submitted By - ****** Table of Contents 1 Remediation Methods for Lead2 1.1 Introduction2 1.2 Sources of Lead3 1.3 Environmental and Health impacts of Lead3 2.0 Removal of Lead from water4 2.1 Conventional Methods of Lead removal4 2.1.1 Ion-Exchange for Lead Removal 2.1.2 Reverse Osmosis 2.1.3 Distillation 2.1.4 Electro Coagulation/ flocculation 2.1.5 Filtration 2.1.6 Use of Iron ions and Precipitation by sulphates /phosphates 2.2 Advanced Studies and Research Methods of Lead Removal 2.2.1 Ammonium Pyrrolidine Dithio Carbamate (APDC) on Symphoricarpus albus  biomass for lead(II) removal 2.2.2 Faujasite Tuff for removing lead 2.2.3 Use of Tridax Procumbens for Removal of Lead 2.2.3 Emulsion Liquid Membrane for Lead removal (ELM) 2.2.4 Lead Removal using Brevundimonas Vesicularis 2.2.5 Use of Copper (II) Polymethacrylate resulting from Gamma Radiation for Lead Removal 2.2.6 Formation of Zeolite from oil shale for Pb Removal 2.2.7 Aluminum Industrial Waste (RED MUD) for removal of Lead 2.2.8 Removal of lead using particulate Slag Columns 2.2.9 Use of Crop Milling Waste for Lead Removal 2.2.10 Removal of Lead using Saponified Melon Peel Gel 2.2.11 Lead Removal from Tap water using POU devices 2.2.12 Use of Magneticenergy of pyrolysis cane bio-chars for removal of Pb 2.2.13 Study of liquid barrier membrane for Removal of Pb 2.2.14 Study on Removal of Lead using Oxidized Multiwall Carbon Nanotubes 2.2.15 Removal of Lead using Saudi Arabian clay 2.2.16 A Study on bigger-pore Diameter Nano Adsorbent for Detection of lead and Removal from Waste water 3.0 Inferences and Critical Opinion for Removal of Lead 4.0 Conclusion 5.0 References Report on Remediation Methods for Lead 1 Introduction Contamination of water with harmful elements is a major issue all over the world. Lead(Pb) the injuriouselement in waste or tap water which contaminates our water supply. The studies carried out in developed countries have reported different adverse symptoms in the discharge sites which includes brain disorder, risk of infertility, birth defects and skin disordersCITATION alD09 \l 1033 (Mathilde Cabral Aminata Toure, 2015) . It is poisonous in nature to biological life specially humans and animals, damages nervous system and major cause of brain disorders. It is neurotoxic and starts accumulating in blood and bones of human body CITATION Dal00 \l 1033 ( Daland R Juberg,, 2000). The chemistry of lead is similar to barium in the body specially accumulation property especially it is accumulated in the bones. CITATION Geo10 \l 1033 (Geological Survey (U.S.), 2010). The effects of lead on fetal are also well known. Since most fetal growth occurs during 90 days period. Studies showed th at increase in lead in the blood is associated with the lead contaminated water intakeCITATION GNg14 \t \l 1033 (G. Ngueta M. PrÃÆ' ©vost, 2014). According to regulations set by EPA (Environmental Protection Agency) the threshold for lead in drinking water is 0.015ppm (or 15 ppb). Lead contamination can also occur through air borne dust. Researchers found that daily exposure of children to Lead (Pb) through house dust was estimated to be 100  mg/day CITATION Kum14 \l 1033 ( Kumiko Yamasaki, et al., 2014). Lead is a toxic metal and can be removed by various different methods. This study is based on the effects of lead and removal methods. 1 Sources of Lead Lead is present everywhere around in the environment. It is present in the form of dust, in metal containers which are lead welded and from natural sources during underground travel of water CITATION YNo01 \l 1033 (Nozaki, 2001). Lead in drinking water comes from corrosion of pipes, solder and alloys of lead plumbing. Lead alloys specially brass and bronze are major sources of lead in water. Leaching of lead in water depends on the quality of water. The pure or distilled water can dissolve lead more easily as compared to tap water CITATION Amy82 \l 1033 (Amy No Clair C. Patterson, November 1982). Therefore the risk involved in the contamination of water with lead is more after the treated water enters the house hold water supply. Studies shows thatPb concentrations ranged from 1 to 52 mg/L, with a mean of 11 mg/L in in the samples taken from the taps CITATION ClÃÆ' ©12 \l 1033 (ClÃÆ' ©ment Cartier Shokoufeh Nour, 15 October 2012). Similarly there is effect of temperature of e nvironment of the concentration of lead in water. During high temperatures more lead is suspected to be leached into the water as compared to low temperature in winter seasonsCITATION GNg141 \t \l 1033 (G. Ngueta M. PrÃÆ' ©vost, December 2014). The areas in vicinity of lead acid batteries are more prone to exposure of lead and the lead levels in blood studied in different research showed the increased values CITATION Cao15 \l 1033 (Suzhen Duan, 2015). 1.2 Environmental and Health impacts of Lead Lead is one of the toxic chemicals to the human, animal and marine life. Lead proliferate in the hard tissues of human bodye.g. bones teeth etc. Studies have shown that the lead accumulation in the bones increases with the age CITATION KBE92 \l 1033 (K. BERCOVITZ D. LAUFER, 1992). In addition to mammals the deposition of lead was found in crops as well. Reports shows that plants have absorbed lead from underground water source and deposited it in seeds particularly those plants whose seed comes in consumption of humans are dangerous for health CITATION Eri15 \l 1033 (Erik Smolders Koen Oorts, 2015). Exposure of lead is usually from oral and respiratory routes. It was found that 10% of oral lead intake is stored in stomach in addition to deposition in bones CITATION Kaa15 \l 1033 (Kaare Lund Rasmussen Lilian Skytte, 2015). Children are more prone to the adverse effects of lead in their body and can absorb 50% of lead through oral intake. CITATION Mat15 \l 1033 (Sakthivel, 2015). The grown up human being may contain lead in the bones if was exposed to lead contaminated water in past. This deposition of lead in bone can also mobilize during pregnancy periods CITATION Kaa15 \l 1033 (Kaare Lund Rasmussen Lilian Skytte, 2015). Lead deposited in blood can retain in it for a month during this period it is filtered through kidneys at a very low rate. Blood level exceeding than 5 µg/dL poses health risk and medical attention is advised at level above 45 µg/dL for adults CITATION Jin15 \l 1033 (Jin-Ha Yoon Yeon-Soon Ahn, 2015). Safe level of lead in the living person depends on age. Children should be cared when level rises above 45 µg/dL. Higher level of lead can cause severe changes in brain functions leading to coma and death (NH Department of Environmental Sciences). Long term exposure to lead can cause joint pain, metallic taste, muscle pains, wrist drop and foot drop like symptoms CITATION Jin15 \l 1033 (Jin-Ha Yoon Yeon-Soon Ahn, 2015). Reproductive and development effects caused by lead are well known. Lead can easily travel through placenta and reach fetus where it can cause miscarriage, still birth and abortion CITATION Xij15 \l 1033 (Xijin Xu Xiaojuan Chen, 2015). It was found that lead has adverse effect on growth of fetus. Weight of fetus is also affected by presence of lead. During the latter stages this lead can affect the mental abilities and intelligence in the new born baby CITATION Jac14 \l 1033 (Jack Caravanos Russell Dowling, 2014). The effects are long lasting and come into notice after several years of birth. "I have therefore selected Lead(Pb) as the pollutant, to be treated/removed from water, in view of its environmental and healthimpacts on human lives, as described above.à ¢Ã¢â€š ¬Ã‚  2 Removal of Lead from water Lead can be removed from water by implying different chemical and physical methods. Chemical methods usually imply some sort of reaction with the lead to make it insoluble in water CITATION Nih04 \l 1033 (Nihal Bekta ¸s Serdar Kara, 2004). Physical methods utilize the techniques of removing lead by filtering out the element using semi permeable membrane like Reverse Osmosis. Advance research on some other methods like adsorption on selective adsorbents is also in progress and will be discussed in detail. 2.1 Conventional Method of Lead Removal Conventional method if used for removal of lead can be useful to an extent and are unable to remove lead completely from water. Few of them as discussed below 2.1.1 Ion-Exchange for Lead Removal Lead is present in the form of Pb+2 in water CITATION Kun15 \l 1033 (Kunashegaran Hamsawahini, 2015).Lead is made to react with chloride ions to form lead chloride which is water insoluble and can be further removed by simple sand filtration method. Lead removal by this method depends on few factors like interaction of lead ions in ion-exchanger unit, functional groups, temperature and cross linking. If complexes in the solution form it will further complicate the ion exchange process CITATION Zbi12 \l 1033 (Zbigniew Hubicki and Dorota KoÅ‚odyÅ„ska , 2012). Limitation of ion exchange method involves the slow kinetics which is the result of poor wetting ability and exposed surface area of aqueous solutions. This results in loss of anions which are responsible for removal of lead. Inter-polymerization technique can be used for improvement in ion exchange CITATION Ryo15 \l 1033 (Ryoko M. Uda, 2015). 2.1.2 Reverse Osmosis Reverse osmosis system utilizes a semipermeable mem...