Make our own biodiesel with new or used oil it is possible although it has certain problems.
In this article I will tell you how to create biodiesel in addition to those problems mentioned, but the first thing to do is to know what we are going to make.
Biodiesel is a liquid biofuel obtained from vegetable oils rapeseed, sunflower and soybeans are currently the most widely used raw materials, although their obtaining with algae crops is also being studied.
The properties of biodiesel are very similar to those of automotive diesel in terms of density and cetane number, although it has a higher flash point than diesel, a characteristic that makes it possible to mix it with the latter for fuel. use in engines.
American Society for Testing and Material Standards (ASTM, international association for quality standards) defines biodiesel as:
"Monoalkyl esters of long chain fatty acids derived from renewable lipids such as vegetable oils or animal fats, and used in compression ignition engines"
However, the most commonly used esters are methanol and ethanol (obtained from the transesterification of any type of vegetable oils or animal fats or from the esterification of fatty acids) due to its low cost and its chemical and physical advantages.
The difference from other fuels is that biofuels or biofuels present the particularity of using vegetable products as raw material, as a consequence it is of vital importance to take into account the characteristics of the agricultural markets.
And therefore, it should be noted that the development of the biofuel industry It does not depend mainly on the local availability of raw material, but on the existence of a sufficient demand.
By ensuring the existence of demand for biofuels, the development of your market can be used to promote other policies such as agriculture, favoring job creation in the primary sector, population fixation in rural areas, industrial development and agricultural activities, and at the same time reducing the effects of desertification thanks to the planting of energy crops.
Rapeseed energy crops
ASTM also specifies various tests that must be carried out on fuels to ensure their correct operation because for the use of biodiesel as an automotive fuel, the characteristics of esters that are more similar to those of diesel must be taken into account. of unmodified vegetable oil.
Advantages and disadvantages of biodiesel
One of the main advantages that we can find from using this biofuel instead of diesel is the Conservation of natural resources of the Earth because it is a source of renewable energy.
Another advantage is the export of biofuelsIn the event that they occur in Spain, in this way our energy dependence on fossil fuels, which is 80%, is also reduced.
Likewise, it favors development and fixation of rural populations that are dedicated to the production of this biofuel.
On the other hand, it helps the decrease in CO2 emissions to the atmosphere, also eliminating the problem of acid rain since they do not contain sulfur.
Being a biodegradable and non-toxic product, it reduces soil contamination and the risks of toxicity in each accidental spill.
Contribute greater security since it has an excellent lubricity and a higher flash point.
As for the drawbacks, we can cite several such as cost. At the moment, it is not competitive with conventional diesel.
Regarding the technical properties, has a lower calorific value, although it does not mean a loss of power or a significant increase in consumption.
On the other hand, it has lower oxidation stability, this being important when it comes to storage, and it has worse cold properties, which makes it incompatible at very low temperatures. However, these last two properties can be rectified by adding an additive.
How we can make our own biodiesel
Get our biodiesel it's very dangerous for the chemical products that we have to use and for this reason I will only say the steps above so that you do not think of doing it at home unless you comply with all the security measures in addition to being legalize in Spain, since it is illegal to produce this biofuel.
The first of all is to start testing with a liter of new oil since this is much easier than used oil, although we intend to give this last oil a second use. When you have control over the new oil you can move on to the used oil and what you would need for now is a blender, keep in mind that you cannot use it for anything else so the blender has to be one of the old ones or a cheap one.
The process
As we have mentioned previously, biodiesel is obtained from fats of vegetable origin, which from a chemical point of view are known as triglycerides
Each of the triglyceride molecules is made up of 3 fatty acid molecules linked to a glycerin molecule.
The intended reaction (called transesterification) for the formation of our biofuel is to separate these fatty acids from glycerin helping us with a catalyst, it can be NaOH or KOH, and thus be able to unite and bind each one of them to a molecule of methanol or ethanol.
Necessary products
One of the products that we are going to use is alcohol. This can be methanol (that forms methyl esters) or ethanol (which forms ethyl esters).
Here the first problem arises since if you choose to make biodiesel as methanol I will tell you that you cannot make this homemade since what is available comes from natural gas.
However, ethanol can be produced at home and what is available comes from plants (the rest from oil).
The downside is that making biodiesel with ethanol is much more complicated than with methanolis certainly not for beginners.
Both methanol and ethanol they are toxic for which you must always keep safety in mind.
They are poisonous chemicals that can blind or kill you, and just like drinking it, it is also harmful by absorbing it through your skin and breathing its vapor.
For home tests you can use barbecue fuel that contains methanol although you must bear in mind that the degree of purity must be at least 99% and if it contains another substance it will not do any good like denatured ethanol.
The catalystAs we have said, they can be KOH or NaOH, potassium hydroxide and caustic soda respectively, one easier to find than the other.
Like methanol and ethanol, soda can be bought easily but is more difficult to handle than potassium hydroxide, which is highly recommended for beginners.
Both are hygroscopic, meaning they easily absorb moisture from the air, reducing their ability to catalyze the reaction. They should always be kept in hermetically sealed containers.
The process is the same with KOH as with NaOH, but the amount has to be 1,4 times higher (1,4025).
Mixing methanol with potassium hydroxide forms the sodium methoxide which is highly corrosive and necessary for the production of biodiesel.
For methoxide, use containers made of HDPE (high-density polyethylene), glass, stainless steel, or enameled.
Materials and utensils (everything has to be clean and dry)
- One liter of fresh, uncooked vegetable oil.
- 200 ml of 99% pure methanol
- Catalyst, which can be potassium hydroxide (KOH) or sodium hydroxide (NaOH).
- Old mixer.
- Balance with 0,1 gr resolution (even better with 0,01 gr resolution)
- Measuring glasses for methanol and oil.
- White and translucent HDPE half-liter container and screw cap.
- Two funnels that fit into the mouth of the HDPE container, one for the methanol and one for the catalyst.
- A two-liter PET plastic bottle (normal water or soda bottle) for sedimentation.
- Two two-liter PET plastic bottles for washing.
- Thermometer.
Security, very important
For this we have to take into account several security measures as well as protective materials such as:
- Gloves resistant to the products that we are going to handle, these must be long so that they cover the sleeves and thus the arms are fully protected.
- Apron and protective glasses to cover the whole body.
- Always have running water nearby when handling these products.
- The workplace must be very well ventilated.
- Do not breathe gases. For this there are special masks.
- There can be no people outside the process, children, or pets nearby.
Can you create biodiesel in any home?
Adding a bit of a joke to so much seriousness in the series "The one coming" looks very easy with the phrase "waving which is gerund" but in reality it is not at all, besides being highly dangerous, and that you have only seen fundamental, the materials.
Without giving many more detailed instructions I can assure you that there is still a lot to do to make biodiesel since first of all a used oil filtering (which is the one that interests us), then we will have to form the sodium methoxide, carry out the necessary reaction, make a transfer and a separation.
We must also check the quality of the product made with the washing test and finally drying.
Homemade biodiesel in Spain
Despite the advantages that biodiesel can present, in Spain is currently illegal to make it at home.
Some countries do allow the production of this biofuel and even sell a manufacturing kit so that anyone with the appropriate security measures can make it.
Personally, here are 2 factors for the illegality of homemade biodiesel.
The first is that Spain cares about us and They have banned its manufacture due to the danger that this entails when handling dangerous chemicals.
The second is that Spain is not interested in the fact that any citizen can produce biofuels for Economic interests.
In any case, it certainly represents a brake towards a possible energy change.