Activated carbon – A type of charcoal processed from a variety of sources of raw materials like ash of peanut shells, coconut shells or coal. Activated carbon is a porous material with many large and small holes. Therefore, the contact area of its surface is very wide to absorb impurities. Activated carbon is widely applied: in health (Carbo medicinalis), it is used to destroy bacteria and toxins after suffering food poisoning.
In the chemical industry, it is used as a catalyst and loading for other catalysts, or to filtered air, filtered water … etc. Demand for activated carbon on the world market is very large, while the activated carbon from coconut shells is produced mostly by the member countries of the Association of Asia Pacific Coconut (APCC), mainly countries such as the Philippines, Indonesia, Sri Lanka, Malaysia, Thailand, India and Vietnam. This is a manufacturing industry that brings more profits for investors and provides a significant source of income for farmers in Ben Tre.
Activated charcoal is useful for deodorizing, removing smoke, filtering toxins … In Vietnam, charcoal is produced much in Ben Tre. Why? Because charcoal is made by burning coconut shells.
The method of creating cheapest charcoal coconut shell is burning coconut shells in condition no oxygen. Raw materials are mainly supplied from the areas where many coconuts are planted such as the southwestern provinces.
Use : destroy toxins in filtering, in water companies, chemicals …
This type of charcoal is absolutely not harmful to the environment and human health. Costs of production are inexpensive ad material resources are abundant.
Activated carbon – a substance consisting mainly of elemental carbon in the form of amorphous (powder), partially in the form of broken graphite crystals (beside carbon, the rest are usually ashes, which are mainly the alkali metals and crushed sand). Activated carbon has a surface area of 500-2500m2 /g (for a specific example for comparison, a tennis court has a large area of about 260 m2). Therefore, it is an ideal material for chemical filtration.
This very large specific surface as a consequence of hollow fiber structure that mainly due to inherited from organic ingredients, going through the dry distillation process at high temperature in anaerobic conditions. Most of the empty– circuit cracked spots have very strong absorption and they act convey grooves (interstitial connector). Activated carbon is often self-upgrade (eg self-cleaning ash or coated surface chemicals), to retain the suction filter attribute in order to be able to absorb the special ingredients such as heavy metals.
What increases the significance of activated carbon is that it is non-toxic substance (including once ingested it), low production costs (charcoal is made from wood and many other waste organic material, for example, from shells, coir), and also, it is very easy to process waste after using (by combustion). If these filtered substances are the heavy metals, the recovery from the burning ash is also very easy.
Applications of activated carbon:
* In Health (Carbo medicinalis): to disinfect and remove toxins after suffering food poisoning.
* In the chemical industry: as a catalyst and loading for other catalysts.
* In the technique: as part of the air filter (in cigarette filters, as well as in the refrigerators and air conditioners).
* In water treatment (or filtered water in the family): to remove trace contaminants.
* Extremely good effect in preventing the harmful effects of earth energy.
How to make activated carbon in living
Nowadays, the shortage of drinking water is becoming more severe. In many places, people have to use water of lakes and rivers and even dirty water. To contribute to improving community health and disease prevention, Courant Vietnam will apply technical guidelines to build simple water filter which its main material is activated carbon. This is a simple filter that every family can do with the cost only from a few hundred thousand Dongs.
Water filter structure is shown in detail in the image below:
Depending on the actual conditions in each family, we can build large pool or small one. Just installed properly according to the diagram instructions and then you willl have a source of fresh water.
From the water you want to filter, you let water go through the shower to make rain (small particles – prevent from eroding the top layer of sand). Through the top layer of sand, water is prefilter types of dirt, creatures and alum. The water leaks through the activated carbon. This layer of activated carbon adsorbs hazardous substances, dangerous microorganisms and neutralizes minerals which are not dissolved well in water. Through activated charcoal, water continues to seep through the layer of coarse-grained sand, the layer of fine gravel and the layer of coarse gravel to come out clean water tank.
According to our experience, you should use plastic water pipes which are drilled holes with a diameter of about 5 li (0.5 cm) along the body tube, head tube inside also been fixed. Thus, water will leak through the small holes, spreading over the tube and not flowing directly into the head tube. This will avoid clogged pipes and the amount of water flow into the pipe is more even.
Besides, one thing you should note that all materials added to the water tank (except charcoal) such as sand, gravel … should be washed before.
Depending on the actual conditions and the state of water resources, every 3-6 months, you should remove the layer of alum on the top layer of sand by: stirring the surface water layer (2-3 cm for water), then open the flowing alum valve above. All layers of alum will be drifting out. Do it twice to clean water completely. Also, if alum contamination situation of water is too heavy, you should replace the top layer of sand after a few months of use. Note: when replacing sand, remember scraping slowly, not to affect the bottom layer of activated carbon (because it is used long term). After 9 months to 1 year, you should replace the entire sand and activated carbon.
Production and application of activated charcoal from bagasse
Every year, the US sugar industry emits 8.6 million tons of bagasse which mostly burned to produce steam, the rest are discarded or used as low-value products. Granular activated carbon (GAC) from bagasse has many advantages over char or activated carbon from bituminous coal is still used as a kind of color reductant for sugar and in other manufacturing processes.
People are researching and considering the capabilities of removing sugar of GAC made from bagasse against other types of activated carbon sold in the market.
Nowadays, they are doing a research of making granular activated carbon (GAC) from bagasse in order to use for many purposes, such as bleaching raw sugar or removing organic contaminants and metal ions in waste water.
The US Sugar Refining Industry uses large amounts of char and GAC from bituminous coal to produce l6.000 tons of refined sugar per day. Both adsorbents are bleaching raw sugar effectively but imported char (as products from cattle bones) are affected by the instability of the international market and bituminous coal is supplied in America but the supply is limited.
Costs for the production of char and GAC from coal are approximately $ 1.21 and $ 4.41 / kg. GAC made from bagasse can be used as color detergents for sugar instead of ones sold in the market. The selling price of this charcoal is lower than char and activated carbon made from coal because of lower production costs.
Bagasse – a byproduct of the sugar companies – in its natural state, it weakly adsorbs organic compounds (such as color of sugar) or metal ions. A method often used to significantly increase the absorption capacity of bagasse is the treatment of materials on surface. The processing is done most effectively by turning bagasse into charcoal. Carbonization process occurs at the same time with the process of the chemical and physical change of bagasse at high temperature in non-oxidizing atmosphere. Granular activated carbon is created by mixing bagasse and different binders in high temperature or pyrolysis. Charcoal is activated in CO2 or water vapor at high temperature.
Bagasse has to be crushed, mixed with a binder, pressed into cakes or pellets to the density of about 1.2 g / cm3; and then pyrolysis, activated and oxidized if necessary.
The presence of different binders in GAC from bagasse has affected its chemical – physical properties. Generally, charcoal from bagasse using molasses binder is not suitable for bleaching process because :
– Being consumed a lot.
– Also contain high ash content.
– The alkali will affect the conversion of cane sugar (sucrose) into glucose and fructose.
To overcome this drawback, the bagasse charcoal is mixed with a binder which is corn syrup. Because of this, the ability to bleach liquid and sugar is also improved This product is being tested to use as alternative types of activated carbon used to bleach raw sugar now.
In addition to the use of activated charcoal for bleaching raw sugar, people are continuing to expand the application to the removal of organic compounds which have low molecular weight and metal ions in industrial waste water. For the trial research, they were using tablet round charcoal, not briquetting charcoal. The results showed that compared with conventional types of activated carbon, bagasse activated carbon adsorbed copper ion better but absorbed organic matter worse. Thus, the possibility of using charcoal produced from bagasse for bleaching raw sugar is very promising. To the United States, the consumption potential of this product is very large.