The increase in industrial, agricultural practices and several anthropogenic activities adds a significant amount of heavy metals in soil and water. Presence of these metals beyond threshold limit is toxic for the flora and fauna of the surroundings. So, there is a need for removing the harmful heavy metals from the environment. Several methods such as precipitation, evaporation, electroplating, ion exchange, membrane processes etc. have been developed for the decontamination of heavy metals from environment. These methods have several disadvantages like unpredictable metal ion removal, high reagent requirement, generation of toxic sludge and many more. To avoid such environmental problem, biosorption has been getting momentum for the removal of pollutants from aqueous medium and soil by the help of biosorbents (bacteria, algae, fungi, plants). Sometimes biosorbents are modified physically, chemically and genetically for the enhancement of their biosorption capacity. The mechanism of biosorption is affected by temperature, pH, bacterial activities and kinetics. This review paper describes the bacterial adsorbents, their modification and mechanism for removal of copper. By comparing previous studies it was observed that highest copper uptake was carried out by chemically modified Thiobacillusferroxidans (198.5 mg/g at pH 5.5 and temperature 30°C) and naturally occurring Pseudomonas putida (96.9 mg/g at pH 6.0 and temperature 37°C).
Keywords: Bioremediation, biosorption, adsorbent, bacteria, heavy metals, copper.
Introduction
Metals are inorganic form of pollutants which are added globally through military, mining, metallurgical, electroplating, metal finishing, agricultural processes and waste disposal. The extensive use of heavy ...
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In this case, the nitrate ion moved from one compound to another as the Cu was replaced by Zn. The zinc dissolved to form zinc (II) ions as the copper (II) ions came out of the solution as copper metal and deposited on the surface of the
The Method of Extracting Copper and Gold by Bacterial Leaching The methods of extracting gold and copper have significant differences and therefore require separate attention. Prior to leaching occurring, either a tailings pile must be built up upon a base of impermeable rock or a series of holes drilled into the ore, to provide access for the bacteriaα. [IMAGE] At process one the bacteria thiobacillus ferro-oxidans and thiobacillus thio-oxidans, naturally occurring bacteria that obtain the energy that they need to survive by oxidising Fe2+ and S2- ionsα, are added to the copper ore. The bacteria in the acidic leaching solution then convert the insoluble sulphide minerals into a solution containing Cu2+, Fe2+, Fe3+ and SO42- ions. The acidic solution provides the optimum pH for the bacteria to work at. Following the bacterial action, the solution is drained off of the impermeable rock or pumped out of the ground through the remaining holes and the remaining solution prepared for concentration and extraction of the Cu2+ ions.
What if there was a way to clean up radioactive waste spills? To clean it out of waters for safe consumption? For years and years people have seen the ways that bacteria can clean up oil spills and nuclear waste, and where baffled on how they did so. How did something so small, clean up a mess so big? Gemma Reguera and her team at Michigan State have solved the age long question. They have decided that bacteria do so by a hair like pili. The pili acts much like a conductive wire, by transferring electrons. Geobacter Sulfurreduncen is one of the many bacteria that do so. The energy conducted by the pili, in turn powers the bacteria. Geobacter, for short, is able to both isolate and, in a sense, kill off uranium in contaminated ground water. So my question is, how effective would it be to clean out mass amount of uranium? First I had to learn about Geobacter and the types of waste created.
The purpose of this lab was to to cycle solid copper through a series of chemical forms and return it to its original form. A specific quantity of copper undergo many types of reactions and went through its whole cycle, then returned to its solid copper to be weighted. We observed 5 chemical reactions involving copper which are: Redox reaction (which includes all chemical reactions in which atoms have their oxidation state changed), double displacement reaction, precipitation reaction, decomposition reaction, and single displacement reaction.
In the first part of this project, two cation elimination tests and one cation confirmation test were performed. 10 drops of 4 cation solutions: potassium, zinc(II), copper(II)
The purpose of this lab is to determine the empirical formula of copper oxide (CuxOy) through a single-displacement reaction that extracts the copper (Cu) from the original compound. In order to do this, hydrochloric acid (HCl) was mixed in with solid CuxOy; the mixture was stirred until the CuxOy was totally dissolved in the solvent. Zinc (Zn) was then added to the solution as a way to enact a single displacement reaction in which Cu begin to form on the Zn; the Cu gets knocked off the Zn through gentle stirring. To isolate the Cu, the supernatant liquid was decanted and the Cu was then washed with first water then second, isopropyl alcohol. Once done, the hydrated Cu is transferred onto an evaporating dish where it was heated multiple times
Our unknown solution, test tube 1024, contained mercury (I) and lead. Throughout the entire experiment, we performed the same reactions in a known solution that contained all three metal ions as a visual comparison to determine what qualities one should observe after each added compound. Because each ion was initially in a compound with nitrate (NO3) in an aqueous, solution we added hydrochloric acid (HCl) to both solutions, and both solutions formed a white precipitate. Because all three metal ions form a white precipitate when bonded with chlorine (Cl‐), it remained unclear which specific ions were present. We then decanted the supernatant and submerged each test tube with the remaining precipitate in a hot water bath. Lead (II) chloride,
The copper cycle has long been studied in laboratories to demonstrate the metal’s versatility. The copper cycle consists of changing a piece of copper through a series of reduction-oxidation, precipitation, decomposition, and acid-base reactions to eventually return it back to pure copper. Research is currently being conducted to further experiment to find more uses for copper. In current medical research, copper has been found to be an effective antibacterial against the growth of E. coli. Medical experts are finally beginning to understand the importance of copper for human health.
Exposure to Mercury (Hg), Copper (Cu) and Lead (Pb) can cause long term health issues. Although, some of the elements may are useful in a rapid growing society they still pose a threat to public health as well as the ecosystem that pertain to wildlife. This research paper was conducted to further explain how these three metals Mercury (Hg), Copper (Cu) and Lead (Pb) have caused public health problems amongst the population while still being used for the greater good of a rising economy.
The Electrolysis of Copper Sulphate Aim Analyse and evaluate the quantity of Copper (Cu) metal deposited during the electrolysis of Copper Sulphate solution (CuSo4) using Copper electrodes, when certain variables were changed. Results Voltage across Concentration of solution electrode 0.5M 1.0M 2.0M 2 5.0 10.6 19.5 4 10.5 19.8 40.3 6 14.3 26.0 60.2 8 15.2 40.4 80.3 10 15.0 40.2 99.6 12 15.1 40.0 117.0 Analysing/Conclusion The input variables in this experiment are; concentration of the solution and the voltage across the electrodes. The outcome is the amount of copper gained (measured in grams) at the electrodes. By analyzing the graph, we can see the rapid increase of weight gained for the 2.0 molar concentration as the gradient is steeper.
Copper works in conjunction with zinc for the formation of digestive enzymes. These enzymes break down the macronutrients found in food and help the body absorb them. They also keep things moving along so that toxins and waste are effectively eliminated from the body.
There are several types of treatment methods present but biological treatment methods have gained much traction in the recent years due to their low operation costs, comparatively benign effects on the environment and their ease of handling and maintenance. Biological wastewater treatment methods can be subcategorized into dispersed growth systems and attached growth systems. Biofilms fall under the latter category (Sehar & Naz, 2016)
Activate sludge system: Using natural biological such bacteria in which they help to remove contaminant.
However, when the pH levels reach a certain stage, the iron can then precipitate out, coating sediments with the characteristic yellow, red or orange colourings (D.E.P. 2, 2002; U.S.G.S. ; U.S.E.P.A., 2002). The rate that A.M.D. advances is also influenced by the presence of certain bacteria (Doyle; U.S.G.S). A.M.D. that has dissolved heavy metals such as copper, lead and mercury can contaminate ground and surface water.
Water pollutants are of different types such as oxygen demanding wastes, disease causing agents, synthetic organic compounds, plant nutrients, inorganic chemicals and minerals, oils, thermal discharge and radioactive wastes. Of all these water pollutants, heavy metals and synthetic organic compounds cause majority of water pollution. Industries like paper and pulp, tanneries, textiles and coke ovens, pha...