The Effect of Addition NPK on Pineapple Peel Fermentation to Produce Bioethanol as a Premium Extender

The depletion of fossil fuels requires alternative energy, one of which alternative energy is bioethanol. Pineapple peel waste has the potential to produce bioethanol because it contains 17.53% carbohydrates and 13.65% sugar which is quite high. The purpose of this study was to produce bioethanol from pineapple peels with the addition of NPK fertilizer as nutrition. The method used is to conduct experiments with the stages: extraction, saccharification, fermentation, distillation, analysis and conclusions. The results obtained were that the highest bioethanol content was obtained in the addition of 20 grams of NPK fertilizer, namely 29.60%


INTRODUCTION
The present energy system is heavily depending on the use of fossil fuels.Facing the challenge of depletion fossil fuels reserves and rising world oil price, many countries has undertaken the initiative to promote the development and dissemination of renewable energy [1].The fuel need is still dominated by petroleum refined products.
Petroleum is still the main driver of the world economy, because industrial equipment and transportation for the distribution of basic needs still uses refined fuels from petroleum.
The petroleum is created by millions of years from fossil and cannot be renewed but the fuel consumption is increasing day by day.It Bioethanol is ethanol produced from living things so that it exists can be created.sugar, while the raw materials are in the form of a sugar solution can be directly fermented [2].The fermentation process also need yeast and in order for growth and for optimal yeast breeding, 4 grams of NPK is added as nutrients into media [1].In Figure 1 shows a garden pineapple that is located in Subang regency.

RESEARCH METHOD
The research using experimental  After that to get ethanol content, a distillation process is carried out [11].The next stage is analysis to measure density, pH and yield to get conclusion.The steps for making bioethanol can be seen in Figure 3 below:

RESULTS AND DISCUSSIONS
The research has been carried out by producing data on the levels of bioethanol contained in the fermented pineapple peel.

Volume 6 ,
Number 2, November 2021 ISSN 2528-2611, e-ISSN 2528-2700 is estimated that oil reserves in Indonesia will only be sufficient to meet consumption needs for the next 18 years.Meanwhile, gas reserves are sufficient for 60 years and coal for about 150 years.Indonesia's oil wells are now drying up due to continuous drilling without being accompanied by exploration or searching for new sources.In 1970s, Indonesia's crude oil production capacity was still in the range of 1.3 million barrels per day (bpd), in 1998 crude oil production rose to 1.5 million bpd, and now Indonesia only able to produce crude oil of 1,070 million bpd or equivalent to production 33 years ago (1972), namely at the time of the industry national oil started to crawl 1.080 million bpd [2].The use of premium fuel can cause the various gasses of emission which are dangerous pollutants in the world.Meanwhile, bioethanol does not emit harmful exhaust gasses because bioethanol is one of the organic synthetic chemicals produced by humans.Bioethanol as a fuel mixture has good prospects because of the increasing world crude oil price so it can be used as an alternative fuel [3].Bioethanol is an appealing energy source as it is clean and produced from renewable sources.It is produced through fermentation by microorganism by one of two methods, distinguished by the raw materials [4][5].
method and was conducted July to September 2019 at the Subang State Polytechnic Laboratory.The step of the research began with collecting data by observation and study of literature about bioethanol, compile research design, experiment of bioethanol in laboratory, and analyze the result of experiment and making the report.The step of the research can be looked in the flow chart at the following Figure 2. The stages of making bioethanol from pineapple peel are extraction process from pineapple peel in order to get the filtrate.The saccharification process need to breakdown the complex sugar in to simple sugar.The next process is the fermentation process, the microorganisms used are Saccharomyces cerevisiae, is a yeast that is commonly used to produce alcohol by fermentation [9].The fermentation process influenced by pH (acidity level), temperature, nutrition (NPK/urea), carbon source, and fermentation time [10].

Figure 1 .
Figure 1.Flow chart the stage of research

Figure 2 .Volume 6 ,
Figure 2. The stages of making bioethanol from pineapple peel The tools that used for making bioethanol are: digital scale, knife, timer, blender, container, measuring cylinder, thermometer, Erlenmeyer flask, volumetric pipette, electric stove, thermo control, reverse cooler, a set of vacuum distillers, alcohol analyzer, separating funnel, volumetric flask, beaker glass, watch glass, dropper, stirrer, filter paper.Materials used

Figure 3 .
Figure 3. Pineapple garden in Subang regency The research was conducted to find the parameters of the weight of NPK fertilizer on bioethanol content give variations in the weight of NPK fertilizer, namely 5 grams, 10 grams, 154 grams, 20 grams, and 25 grams.The weight of pineapple peel is 500 grams, the amount of water is 1000 grams, the weight of yeast is 14 grams and the fermentation time is 4 days.This research was conducted 5 times each of the addition of NPK fertilizer nutrients that were added during fermentation to obtain the highest average bioethanol content.The results of the research are as follows: that the amount of 20 grams of NPK fertilizer contains the most optimal average bioethanol content of 29.60%, while the amount of 5 grams of fertilizer contains the lowest average bioethanol content of 20.00%.This happens because the nutrients provided by NPK fertilizer during the fermentation process are not in accordance with the needs.The amount of 25 grams of NPK fertilizer contains bioethanol levels on average of 20.80%, there is a decrease, and this is because the nutrients given during the fermentation process are excessive so the fermentation process is not optimal.The several steps for making bioethanol can be seen in the following Figure:

Figure 4 .Figure 5 .
Figure 4.The pineapple peel Pineapple Peel is washed to clean from dirt.Then ready to be weighed, then crushed.

Figure 6 .
Figure 6.The pineapple pulp Peel pineapple that has been crushed, then measured according to the desired size.The relation between the addition of NPK nutrient mass to ethanol concentration is that the higher addition of NPK (up to 2%), so that the higher the ethanol produced, because the bacteria Saccharomyces cerevisiae requires nutrients like nitrogen and phosphorus for the growth[13][14].Production of

Table 1 .
The result of experiment Based on the table above, it can be seen