Friday, December 7, 2012

Heavy Metal Waste

Development activities aimed at improving the welfare of the people who carried out through long-term development, which is based on the development in the industry. Industrial development in the party will produce useful goods for public welfare and on the other hand, the industry also produces waste. Among the waste generated by industrial activities are B3.

Hazardous and toxic waste (B3) is the remnant of a business and or activities that contain hazardous or toxic and because of the nature and amount or concentration and or, either directly or indirectly and can pollute or damage the environment, and may be dangerous or environment, health, human survival and other living creatures (PP. 18 Year 1999 Jo PP. 85, 1999.

Heavy metals are natural components of the environment are gaining attention due to excess is added to the soil in amounts increased and the possible dangers posed. Heavy metals refers to metals that have a higher density of 5 or 6g/cm3. But in fact within the meaning of these heavy metals, also included metalloid elements that have hazardous properties such as heavy metals that amount totaled approximately 40 species. Some of these toxic heavy metals are As, Cd. Cr, Cu, Pb, Hg, Ni, and Zn.

In general, heavy metal has been used widely, especially in chemistry and industry. According Palar (1994), heavy metals generally have the following characteristics:

a. has a good ability as a conductor of electricity (conductors)
b. have a high density.
c. Can form alloys with other metals
d. For heavy metals can be forged and shaped

Elements or contained metal content in the atmosphere is found in the form of particles or a compound. Metallic element found widely across the earth's surface that can be toxic to humans if dangerous entry into the body where the metal is usually found in food, water and air.

Chromium (Cr)
Chromium (Cr) is a hard gray metal. Chromium present in the glass industry, metal, photography, and electroplating. In industry, chromium is needed in two forms, pure chromium and chromium irons alliance called ferokromium whereas pure chromium metal is never found in nature. Chromium itself is actually not toxic, but its compounds are highly irritant and corrosive. Inhalation of chromium can cause damage to the nasal bone. In the lungs, chromium can cause cancer. For heavy metals, including chromium metal has a high toxicity. Toxicity owned by chromium is determined by the valence of the ion. Metal Cr6 + is the most widely studied due to its toxic nature Cr6 + is a powerful toxic and can result in acute poisoning and chronic poisoning. (Soemirat, 2002).

Chromium has the electron configuration 3d54s1, very hard, has a melting point and a high boiling point above the melting point and the boiling point of the transition elements of the first row of the other. Important oxidation states of +2, +3 and +6. if in pristine condition with very slow dissolves in dilute acid to form salts of chromium (II). (Achmad, Hezekiah, 1992).

The compounds can be formed by chromium have different properties according to its valence. Compounds are formed from metal Cr +2 will be alkaline, in an aqueous solution of chromium (II) is a strong reductant and easily oxidized in air to a compound of chromium (III) by the reaction:

2 CR2 + (aq) + 4H + (aq) + O2 (g) + 2 Cr3 + (aq) + 2 H2O (l) ........... (1)
Compounds that form ions chromium (III) or Cr 3 + ion is amporter and is the most stable among the other transition metal cations as well as in solution, these ions exist as () [] +362 OHCr green. Compounds are formed from metal ions Cr6 + will be acid. Cr3 + can be precipitated in the form of hydroxide. Chromium hydroxide is not soluble in water at optimal conditions of pH 8.5 to 9.5 but will dissolve higher at low pH or acidic conditions. Cr6 + is difficult to settle, so the handling of the reducing agent required to Cr3 + Cr6 +. (Palar, 1994).

Zinc (Zn)
Zinc (Zn) is obtained metal among others in alloy industry, ceramics, pigments, rubber, and others. Substantially lower Zn toxicity. The body needs zinc for metabolic processes, but high levels can be toxic. Zinc causes water color becomes opalescent, and when cooked will arise sediments such as sand. (Soemirat, July, 2002).

Zinc is a Bluish-white, shiny metal, Zinc is a metal such as silver is widely used in the stainless steel industry in order, to make brass, making heat-resistant cans and so on. Brittle at ambient temperature but soft at a temperature of 100-150 ° C. It is a konduktur electricity and burning high in the air on a red-hot glow.

Metal zinc (Zn) are available commercially so it is not up to par to make it in the laboratory. Most production of zinc sulphide ore based. Zn roasted in industrial plants to form zinc oxide, ZnO. This reduced with carbon to form zinc metal, but needed practice ingenious technology to ensure that the resulting zinc oxide containing impure.

ZnO + C ? Zn + CO ......................... (2)
ZnO ? Zn + CO + CO2 ......................... (3)
CO2 + C ? 2CO ......................... (4)

Another type of extraction is electrolytic. Decomposition of crude zinc oxide, ZnO, in sulfuric acid to zinc sulfate, ZnSO4. Elektrolisi ZnSO4 solution of using aluminum cathode and silver anode mixed with tin to form pure zinc metal coated aluminum. Oxygen gas liberated at the anode.

Copper (Cu)
Copper with the chemical name cupprum denoted by Cu. The metal is shaped crystal with a reddish color. In chemistry, the compounds formed by Cu (copper) has a valence number +1 and +2 are insoluble in cold water or hot water, but they can be dissolved in acid solution. Cu is the best conductor of electricity after silver (Argentum-Ag), Cu therefore widely used in the field of electronics or electrification. In humans, the effects of poisoning caused by exposure to dust or fumes. Cu was atrophic damage to the mucous membranes associated with the nose. Damage that is the result of a combination of irritating properties owned by the Cu dust or vapor. (Palar, 2004).

In general, sources of Cu entry into the environment is a natural order and non-natural. Here is the entry of Cu into nature:

a. Cu naturally fit into an order of the environment as a result of natural events. This element can be derived from the erosion events (erosion) from mineral rocks, from the dust or particulates and Cu are present in the layer of air that goes down with rain.

b. In non-natural Cu into an order of the environment as a result of a human activity. Pathways of human aktfitas to include Cu into the environment there are a variety of ways. One way is to discharge by industries that use Cu in the production process.

Lead (Pb)
Lead or in everyday life known as the lead, in scientific language called Plumbum. Formerly used as a constituent in the paint, batteries, and is currently widely used in gasoline. Organic Pb (TEL = Tetra Ethyl Lead) intentionally added to gasoline to increase the octane rating. Pb is a systemic poison which is known by way of revenue every day can be through food, water, air and tobacco smoke inhalation. The effects of Pb poisoning can cause brain damage and diseases associated with the brain, such as epilepsy, hallucinations, brain damage is great. (Palar, 2004).

Lead is used in industry as a coating material for crafting materials from the soil because of the low temperature coating materials can be used. Now many are also used as a coating tapes, because they have the attitude resistant to corrosive materials and battery materials, paint. The most important compounds are (CH3) 4PB and (C2H5) 4PB made in large quantities for use as an "antiknock" in the fuel.

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