VANOS 
JOURNAL OF MECHANICAL ENGINEERING EDUCATION
http://jurnal.untirta.ac.id/index.php/vanos
ISSN 2528-2611, e-ISSN 2528-2700
Vol.2, No.2, Desember 2017, Hlm.x-x.

THE EFFECT OF ZEOLITE CATALYSIS SIZE ON BIODIESEL CHARACTERISTICS OF TUNA FISH WASTE BIO-OIL
Imron Rosyadi1, Ni Ketut Caturwati2 , Haryadi3, Syahrul Ivandy4
1,2,3Mechanical Engineering, Engineering Faculty, Universitas Sultan Ageng Tirtayasa
Jl. Jenderal Sudirman KM 03 Cilegon 42435
E-mail: imron_jtm@untirta.com

Abstracts
Indonesia is a country with the third largest tuna production in the world. Fish oil as a fishery product processing waste is a potential material for making biodiesel because it has a high fat content. In this research, biodiesel was made from tuna waste bio-oil through esterification and transesterification processes at 60 ° C, stirring speed 360 rpm with a reaction time of 2 hours. The purpose of this study was to determine the levels of Free Fatty Acid (FFA) contained in bio-oil from tuna waste and to determine the effect of the size of the natural zeolite catalyst in the transesterification process on the characteristics of the biodiesel produced. The variables used were the size of the zeolite catalyst 10 - 20, 30 - 40, 50 - 60, 70 - 80, 100 - 120 mesh. From the research results, it can be concluded that the smaller the zeolite catalyst size, the resulting biodiesel is closer to the biodiesel standard and the size of 100-120 mesh which is very close to the SNI 7182: 2015 biodiesel standard with a density value of 849.6 kg / m3, kinematic viscosity 3,413 cSt, moisture content. 0%, acid number 1.10 mg.KOH / gr, flash point 75 ° C, calorific value 8.240 Cal / gr.

Keywords:    Tuna Fish, Catalyst, Biodiesel, Characteristics

1.	INTRODUCTIO 
1.1	 Background
The growing need for oil is a challenge that needs to be anticipated by finding alternative sources of energy. Petroleum is a non-renewable energy source, it takes millions or even hundreds of millions of years to convert petroleum raw materials into petroleum, an increase in the amount of petroleum consumption causes the depletion of petroleum. Of the various petroleum refined products used as fuel, the most widely used is diesel fuel, because most transportation means, agricultural equipment, heavy equipment and propulsion of power generators use this fuel..
Indonesia is the world's third largest producer of tuna fisheries, with a contribution of 16 percent of the world's tuna fishery products (FAO and SOFIA / State of World Fisheries and Aquaculture, 2018). Based on statistical data from the Ministry of Marine Affairs and Fisheries in 2011, in Indonesia there are around 114 fish canning companies. Total National Fishery Production is 23.26 million tons, of which captured fisheries are 6.04 million tons, aquaculture is 17.22 million tons (Central Statistics Agency, 2017). One type of fish that is widely produced is Tuna, in 2016 the production of tuna in Indonesia was 1,129,375 tons (GREENPEACE, 2018).
Fish oil as one of fishery product processing wastes is a potential material for making biodiesel (environmentally friendly fuel) because it has a high fat content. The advantage of fish oil when used as a raw material for biodiesel is that apart from having a higher variation of fatty acids compared to other oils or fats, it also has a higher amount of fatty acids. Fish oil carbon chain length reaches 22 and contains more types of unsaturated fatty acids. In principle, there are 3 types of fatty acids derived from fish, namely saturated, monounsaturated and plural unsaturated. Monounsaturated fatty acids contain one double bond and polyunsaturated fatty acids contain many (up to 6) double bonds per molecule (Wahyudi, at.all, 2016).
Previous research conducted by Hartono et al. (2017) where the results of research on making biodiesel using bayah banten natural zeolite as a heterogeneous catalyst can produce biodiesel with results that meet SNI at an optimum temperature of 60 oC. Another research that has been conducted by Sukiman Hernanda, et al (2014) where the biodiesel from baung fish waste can be directly used in diesel engines because the physical and chemical properties meet the characteristics of biodiesel or the Indonesian National Standard.  (SNI).

1.2	Problem Formulation
Based on the background of the problems above, the following problems can be formulated :
1.	What is the level of Free Fatty Acid (FFA) contained in bio-oil from tuna waste ?
2.	How is the effect of size variations 10 - 20, 30 - 40, 50 - 60, 70 - 80, and 100 - 120 mesh of catalysts used on the characteristics of biodiesel from tuna fish waste oil ?

1.3	 Scope
The scope of this research consists of :
1.	1. The raw material used is tuna fish oil waste.
2.	2. The catalyst used by Bayah's natural zeolite.
3.	3. The transesterification reaction time used is 2 hours.
4.	4. The temperature of the transesterification reaction used is 60 oC.
5.	5. The speed of stirring the transesterification reaction used is 360 rpm.
6.	Comparison of methanol with bio-oil 6: 1.
7.	The test is carried out to calculate the FFA content of the raw material and the characteristics tested are viscosity, density, moisture content, flash point, heating value, and acid level..

1.4	Objective
The objectives to be achieved from this research are :  
1.	Mengetahui kadar Free Fatty Acid (FFA) yang terkandung pada bio-oil dari limbah ikan Tuna.
2.	Mengetahui pengaruh variasi ukuran 10 - 20, 30 - 40, 50 - 60, 70 - 80, dan 100 - 120 mesh katalis yang digunakan terhadap karakteristik biodiesel dari minyak limbah ikan tuna.
1.5	Research Benefits
The benefits of this research are : 
1.	Produce alternative fuels from tuna bio-oil waste.
2.	Understand the effect of variations in the size of the catalyst mesh used on the characteristics of biodiesel from tuna fish waste oil.

2.	BASIS OF THEORY
2.1	Tuna Fish
Tuna fish (Thunnus sp) is a group of fish which is the prima donna of marine consumption fish exports from Indonesia. FAO official data through SOFIA in 2016 showed that 7.7 million metric tons of tuna and species such as tuna were caught worldwide. In the same year, Indonesia succeeded in supplying more than 16% of total world production with an average production of tuna, skipjack and tuna reaching more than 1.2 million tons / year. Meanwhile, the export volume of Indonesian tuna reached 198,131 tons with a value of USD 659.99 million in 2017. (Minister of Marine Affairs and Fisheries of the Republic of Indonesia, Bali Tuna Conference 2018).
Tuna is one of the most economically valuable fish in the world and also an important predatory species in marine ecosystems. The tuna industry provides thousands of jobs in the fishing, processing and trade sectors worldwide, including in many coastal developing countries, and generates significant income. In 2016, Indonesia was ranked first in the world in tuna production, namely 1,129,375 tonnes (GREENPEACE, 2018).
The abundant fish waste, which is around 20-30% can be used again, because it still has a high enough oil content, fish waste contains a lot of very long chain fatty acids with more than 20 carbon atoms, most of which have 5-6 double bonds (Samosir and Fadriyan, 2012).

2.2	Biodiesel
2.3	Biodiesel merupakan energi alternatif pengganti solar yang berasal  dari nabati atau hewani yang merupakan bahan terbaharukan (renewable). Biodiesel secara umum adalah bahan bakar mesin diesel yang terbuat dari bahan terbarukan atau secara khusus merupakan bahan bakar mesin diesel yang terdiri atas ester alkil dari asam-asam lemak. 
2.4	Biodiesel tersusun dari berbagai macam ester asam lemak yang dapat diproduksi dari minyak tumbuhan maupun lemak hewan. Minyak tumbuhan yang sering digunakan antara lain minyak sawit (palm oil), minyak kelapa, minyak jarak pagar dan minyak biji kapok randu, sedangkan lemak hewani seperti lemak babi, lemak ayam, lemak sapi, dan juga lemak yang berasal dari ikan.
2.5	Proses pembuatan biodiesel dapat melalui reaksi esterifikasi-transesterifikasi atau hanya reaksi transesterifikasi. Berdasarkan penelitian yang telah dilakukan, bahwa bahan bakar biodiesel memiliki sifat fisika dan kimia yang hampir sama dengan bahan bakar diesel konvensional dan juga memiliki nilai energi yang hampir setara tanpa melakukan modifikasi pada mesin diesel. Penggunaan biodiesel di Eropa dilakukan dengan mencampur bahan bakar biodiesel dengan diesel konvensional dengan perbandingan faktor teknis pada mesin terhadap produk baru serta menjaga kualitas bilangan setana biodiesel yang harus sama atau lebih besar 40 (Arpiwi, 2015).
The advantage of biodiesel is that it is an environmentally friendly alternative fuel because it can reduce carbon monoxide (CO) and carbon dioxide (CO2) gas emissions and is free of sulfur content compared to other petroleum materials. Biodiesel can be used as a diesel fuel mixture and can be applied without engine modification. The following is a comparison of the characteristics of biodiesel with diesel oil.

2.6	Esterification and Transesterification Reactions
Esterification reaction is a reaction between fatty acids and alcohols to produce esters and water with the help of an acid catalyst. The esterification reaction is a reaction that is reversible.
The transesterification reaction is also a reversible reaction, so that when the reaction has reached equilibrium, the reaction can shift back towards the reactants. In the transesterification reaction, it takes a long time and a high temperature of about 250 oC without the help of a catalyst. Therefore the catalyst will help speed up the reaction rate in the transesterification reaction.
The esterification process with an acid catalyst is needed if the oil contains FFA above 5%, if the oil with an FFA content of more than 5% is transecetrified directly with an alkaline catalyst, the FFA will react with the catalyst and will form soap. Soap formed in large enough quantities can inhibit the separation of glycerol from biodiesel and result in the formation of emulsions during the washing process. So esterification is used as a preliminary process to convert FFA into methyl ester so as to reduce the FFA level in vegetable oil and then transesterification with an alkaline catalyst to convert triglycerides into methyl esters (Hikmah, 2010).

Figure 1. Esterification Reaction

Figure 2. Transterification Reaction

2.7	Zeolit
Zeolite is a good catalyst because it has large pores with a wide surface and also has an active side. The presence of an intracrystalline cavity, zeolite can be used as a catalyst. The catalytic reaction is influenced by the size of the mouth cavity and the flow system, because this reaction depends on the diffusion of the reagent and the reaction results (Hartono, 2017). Zeolite has the following properties  :
1. Dehydration Properties of Zeolite
This property has an influence on its adsorption properties. Zeolite can release water molecules from the cavity of the pores when heated. Water molecules are released reversibly, zeolites can bind water molecules back in a reaction.
2. Adsorption properties
Zeolite has a high capacity as an adsorbent to absorb water, gas, and smaller molecules. Zeolite absorption depends on the amount of surface area of ​​the pores.
3. Ion Exchange Properties
The zeolite's ability to exchange ions depends on the number of cations exchanged on the zeolite. The nature of this ion exchanger depends on the size of the cavity in the zeolite, Si / Al ratio, ion volume and temperature. The larger the cavity, the greater the ion-exchange properties.
4. Nature of Catalyst
Zeolites can be used as catalysts in catalytic reactions. Zeolite has an empty space in the form of an active channel in it. If zeolite is used in the catalysis process, the molecular diffusion process will occur into the free space between the crystals and chemical reactions also occur on the surface.
5. Filter Properties
Zeolites have properties that can filter and separate mixtures of molecules based on differences in size, shape, and polarity of the filtered molecules..
                                             
3.	Metodology
This research was conducted at the Manufacturing Engineering Laboratory, Mechanical Engineering Department, and Basic Chemical Laboratory, Chemical Engineering Department, Engineering Faculty, Sultan Ageng Tirtayasa University, Cilegon, Banten. The research methodology used is literature study method and experimental method. 

3.1	Flow Chart

Start

Study of literature

Preparation material

Process of Refining Size Catalyst 10-20, 30-40, 50-60, 70-80, dan 100-120 Mesh

Activation Catalys

Eseterificatio n process
(Bio-oil +  + Methanol 98%)
(1400 ml + 0,5 %  Bio-Oil mass  + 30% Volume Bio-Oil)

Analisa Kadar Asam Lemak Bebas (FFA)

> 5%

FFA < 5%

Biodiesel production  (Transesterification)
 (Bio-oil + H-Zeolit + Methanol 98%)
250 ml +  10% Berat Bio-oil + 1500 ml

A

A

100-120 Mesh

70-80 Mesh

30-40 Mesh

10-20 Mesh

50-60 Mesh

Biodiesel Purification Using Aquadest 60 ºC and Removing Moisture Content

Sample Testing and Data Collection (Viscosity, Density, Flash Point, Water Content, Acid Value and Calorific Value)

Analysis data

Finish

Conclusion

Figure 3. Flow Chart

3.2	Research Procedure
1.	1. Start Research.
2.	2. Studying the literature on supporting research theories.
3.	3. Prepare tools and raw materials for bio-oil from fishery waste processing in the Muara Angke area, North Jakarta.
4.	4. Smoothing the catalyst by mashing the zeolite from the chunks into smaller sizes, then sieving it with a mesh sieve of 10 - 20, 30 - 40, 50 - 60, 70 - 80, and 100 - 120 mesh.
5.	5. Activation of natural zeolite catalyst in each size of 10 grams is immersed in 100 ml of 1N H2SO4 solution and heated for 60 minutes at 120 ° C. Then washed several times, dry at 110 ° C for 2 hours.
6.	6. Analysis of free fatty acid (FFA) levels is carried out by adding 50 ml of 98% ethanol to 2.5 grams of tuna fish waste bio-oil, then heating it to a boil while stirring for 10 minutes. Next, add 2-3 drops of the phenoftalein indicator solution and shake the mixture. Tritrate with the drops with 0.1N KOH until the color of the solution is constant pink for 10 seconds. After obtaining the required 0.1N KOH volume, calculate the FFA level.
7.	7. The esterification process is carried out when the free fatty acid content in the raw material is more than 5%. This process aims to reduce levels of free fatty acids in raw materials, done by adding a mixture of Bio-oil 1400 ml + H2SO4 0.5% by weight of bio-oil + Methanol (98%) 30% by volume of bio-oil, then heating it to a temperature. 60 ° C and stirring speed of 245 rpm for 1 hour.
8.	8. The transesterification process is carried out by mixing 250 ml of tuna fish waste bio-oil with 1500 ml methanol plus bayah natural zeolite which has been activated 10% of the bio-oil weight. Heated at 60 ° C while rotating at 360 rpm for 2 hours.
9.	9. Washing the biodiesel product using distilled water with a temperature of 60 ° C and then removing the moisture content after the purification process.
10.	10. Testing the characteristics of biodiesel which includes density, viscosity, moisture content, flash point, calorific value, and acid level at the Basic Chemistry Laboratory, Department of Chemical Engineering, Faculty of Engineering, Sultan Ageng Tirtayasa University.
11.	11. Data collection was carried out after completing the characteristic testing of the Basic Chemistry Laboratory, Department of Chemical Engineering, Faculty of Engineering, Sultan Ageng Tirtayasa University.
12.	12. Analyze the results obtained from the biodiesel characteristics test and then proceed to make the final report.
13.	13. Conclude the results of the analysis of the research on the effect of the size of the natural zeolite catalyst.

4.	RESULT AND DISCUSION
4.1	Analysis of Tuna Fish Waste Bio-oil Free Fatty Acid Levels
Calculating the levels of ALB contained in raw materials using the following formula :
Percentage  ALB (%) =  x 100 %

                           =  x 100%

                              = 33,84 %
Where :
V = volume of KOH required in the sample titration (ml)
N = Normality of KOH solution
M = molecular weight of dominant fatty acid (oleic acid is 282)
m = sample weight (gr)
The levels of Free Fatty Acids (FFA) contained in the Tuna waste bio-oil were 33.84%. The high level of FFA is due to the decay that occurs in the raw material, so the esterification process is needed to reduce the free fatty acid content. After esterification, the free fatty acid content is obtained with the formula :
Persentage ALB (%) =  x 100 % 

                                           =  x 100 %

                                           = 4,85 %

The level of free fatty acids (FFA) contained in the tuna waste bio-oil after the esterification process is equal to 4,85 %..

4.2	Analysis of Biodiesel Yield Characteristics
1.	Density Analysis	
Based on the graph in Figure 4, it can be seen that the smaller the size of the zeolite catalyst, the density value obtained increases, but it does not meet the requirements of SNI 7182: 2015 biodiesel because the triglycerides that have not been completely converted into methyl esters can be caused by poor biodiesel manufacturing processes.

Figure 4. Effect of Catalyst Mesh Size on Biodiesel Density Value

The resulting biodiesel density value is relatively low because the ratio of methanol to bio-oil is more methanol (6: 1) so that the density is lower and is closer to the methanol density of 0.7918 kg/m3. In Sample B70.80 (841.0 kg / m3 ) and B100.120 (849.6 kg / m3) it is close to SNI 7182: 2015 biodiesel requirements. 

2.	Viscosity Analysis
Based on the graph in Figure 5, it can be seen that the effect of the size of the zeolite catalyst on the kinematic viscosity value of the resulting biodiesel forms a fluctuating pattern but tends to increase following the increase in the biodiesel density value. 

Figure 5. The Effect of Catalyst Mesh Size on the Viscosity Value of Biodiesel
The viscosity value produced by this biodiesel has met the SNI 7182: 2015 biodiesel standard.
This is important, considering that viscosity is a parameter of fuel resistance to flow. A viscosity that is too high will complicate the flow of fuel and can result in incomplete combustion, whereas if it is low it allows leakage and does not have enough lubrication at the injection pump.. 

3.	Water Content Analysis

Figure 6. Effect of catalyst mesh size on moisture content of biodiesel

Based on the graph above, it can be seen that the use of zeolite catalysts greatly affects the desired product yield target, one of which is the moisture content value which does not exist at all in the biodiesel yield. Due to the nature of activated zeolite, it is dehydrated when heated, which results in the zeolite's pores having no water content and is reversible or can re-tie water in the pores during the transesterification process.
In addition, the moisture content of biodiesel is more influenced by the moisture content in the raw material and the process of removing water content during the biodiesel refining process. Based on the measurement of moisture content, all samples have met the SNI 7182: 2015 biodiesel standard.

4.	Analysis of Acid Numbers 

Figure 7. Effect of catalyst mesh size on acid number of biodiesel

Based on the graph in Figure 7, it can be seen that the size of the zeolite catalyst is getting smaller, expanding the surface of the zeolite, carrying out adsorption power to absorb a number of free fatty acids in biodiesel because of the ability of the silicate compounds present on the zeolite surface to play a role in the adsorption of water and organic compounds. This has an effect on reducing the acid number of biodiesel. The value of the acid number produced by biodiesel does not meet the SNI 7182: 2015 biodiesel standard. The acid number is influenced by the composition of the fatty acid constituents of the raw material, because the raw material from decaying waste has a high acid value..

5.	Flash Point Analysisi
Based on the graph in Figure 4.8, it can be seen that the effect of the smaller zeolite catalyst size on the flash point value forms an upward pattern but is not significant and the flash point value produced by the biodiesel does not meet the SNI 7182: 2015 biodiesel standard. 

Figure 8.  Effect of Catalyst Mesh Size on Biodiesel Flash Point

Hal ini dikarena terkonversinya trigliserida menjadi metil ester belum sempurna dan kemurnian biodiesel yang dihasilkan kurang baik. Nilai  flash point cenderung rendah, hal ini bisa dikarenakan perbandingan methanol dengan bio-oil terlalu besar methanol (6 : 1) yang mengakibatkan flash point hasil biodiesel lebih rendah, karena titik titik nyala methanol rendah sekitar 11 – 15,6 °C.

6.	Caloric Value Analysis

Figure 4.9 The Effect of Catalyst Mesh Size on the Calorific Value of Biodiesel

Based on the graph in Figure 4.9, it can be seen that the effect of the smaller zeolite catalyst size on the heating value of biodiesel forms a fluctuating pattern but tends to increase. This is because the smaller the zeolite catalyst size will increase the surface area of the catalyst which causes the faster reaction rate and multiply the mass transfer rate of the reactants into products. The calorific value of the biodiesel has not met the SNI 7182: 2015 biodiesel standard because the conversion of triglycerides to methyl esters is not yet complete. The calorific value of the resulting biodiesel tends to be low, this can be due to the too large ratio of methanol to bio-oil (6: 1) which can affect the calorific value of biodiesel which tends to approach the calorific value of methanol 5827.83 Kal / gr.

5. CONCLUSION
Based on the research that has been done, conclusions can be drawn as follows :
1.	The level of Free Fatty Acid (FFA) contained in the bio-oil raw material from tuna waste was quite high, namely 33.84%.
2.	Density
All samples have not met the SNI 7182: 2015 biodiesel standard, but the B70.80 (841.0 kg / m 3) and B100.120 (849.6 kg / m 3) samples are close to the SNI 7182: 2015 biodiesel standard. . It can be concluded that the smaller the zeolite size, the closer the density value of SNI 7182: 2015.

3.	Viscosity
It can be concluded that all samples meet the SNI 7182: 2015 biodiesel standard, with the smallest value being sample B10.20 (3.205 cSt) and the largest sample being B70.80 (3,448 cSt).
4.	Water content
All samples met the SNI 7182: 2015 biodiesel standard, with a moisture content value of all samples of 0% or not containing water at all. It can be concluded that the use of zeolite catalyst has an effect on the value of the resulting moisture content.
5.	Flash Point
All samples have not met the SNI 7182: 2015 biodiesel standard, with the smallest value being 66 °C and the greatest being 75 °C. It can be concluded that the smaller the zeolite size, the greater the resulting flash point value.
6.	Calorific Value
All samples have not met the SNI 7182: 2015 biodiesel standard, but the sample B10.120 (8,240 cal / gr) is close to the SNI 7182: 2015 biodiesel standard. It can be concluded that the smaller the zeolite size, the greater the resulting calorific value.
7.	Acid Numbers
8.	All samples have not met the SNI 7182: 2015 biodiesel standard, with the smallest value being 1.10 mg.KOH / g and the largest being 2.35 mg.KOH / g. It can be concluded that the smaller the zeolite size, the smaller the value of the resulting acid number. The acid number is influenced by the fatty acid composition of the raw material.

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