KINETIKA DESORPSI UREA DARI KARBON BERPORI TEROKSIDASI ASAM SULFAT SEBAGAI SLOW RELEASE FERTILIZER

Urea is an important nitrogen source for plant but the price of urea fertilizer is relatively high. Urea uptake from urea manufacture waste water and its application as fertilizer is of high interest. The purpose of this study is to find out desorption ability of urea adsorbed porous carbon to be applied as fertilizer. Theoritically, urea released from  porous carbon to environment has slower rate of mass transfer compare to conventional urea fertilizer because urea molecules in porous carbon has to pass through pores of carbon during its movement out of carbon. The porous carbon as adsorbent was made from coconut shell by pyrolysis, followed by sulfuric acid oxidation treatment  Oxidation treatment carried out to extent adsorption capacity as well as to give additional sulfur nutrient when applied as fertilizer. Oxidation of carbon surface was performed using sulfuric acid (50%w) to soak porous carbon followed by heating at 90oC temperature for 2 hours. Desorption was conducted by placing porous carbon into beaker contain water and the raising of urea concentration in water recorded after 3,5,10, 30, and 60 minutes. Results reveal that the value of mass transfer coefficient (kc) and effective diffusivity (De) of urea desorption from porous carbon are 0,0293 – 0,0743 cm/s and 8 x 10-10 – 5 x 10-9 cm2/s with initial concentration of urea 1000, 2000, and 4000 mg/L. Release rate of urea from porous carbon and urea prill are 0,07 ppm/s  and 1,23 ppm/s. Slower release rate of urea off  porous carbon than urea prill shows the promising of urea recovery using porous carbon as slow release fertilizer

PENGARUH AMONIA DALAM LARUTAN TERHADAP KAPASITAS ADSORPSI UREA DENGAN KARBON BERPORI

Urea is a primary nitrogen source for plant. Conventional urea fertilizer is made from reaction between ammonia and carbon dioxide. Wastewater of urea manufacture usually contains urea ammonia in a high concentration. They can be as high as 650-4000 ppm urea and 100 – 1300 ppm ammonia/m3 wastewater. High concentrated urea and ammonia disposal to environment may lead to eutrophication in aquatic ecosystem which cause adverse impact to aquatic organism. Therefore, treatment to take urea up from urea manufacture wastewater is of interest that give double benefits : reduce urea from wastewater to meet an environmentally safe condition and obtain a low cost urea fertilizer for plant. The purpose of this study is to determine urea adsorption capacity of porous carbon in aqueous solution contains ammonia. The porous carbon as adsorbent was made from coconut shell by pyrolisis. Oxidation treatment of carbon surface was performed using sulfuric acid (50%w) at 90oC temperature for 2 hours. The adsorption was conducted at room temperature with initial urea concentration in the range of 500-8000 ppm using urea-ammonia solution as simulation liquid. Results reveal that urea adsorption capacity increase significantly 41%.in urea-ammonia solution compare to urea solution, that is in the range of 27-444 mg/g carbon

Pengaruh Variasi Rasio Perekat Terhadap Nilai Kalor Briket dari Ranting Kayu dan Sekam Padi

Wood twigs are solid waste that is usually used as fuel. However, people prefer to use LPG gas as a heat source for daily cooking. Wood twigs are rarely used by the community as a source of fuel. Around Kamulyan Beach Cilacap there are scattered wooden branches. In Cilacap Regency there is agricultural waste, especially in rice fields, namely husk waste. Experiments to increase the use of beach wood husks and twigs as materials for making briquettes with 10%, 15%, and 20% tapioca flour adhesives. The purpose of this study is to determine the effect of variations in adhesive portions in percent of a briquette on its heating value. Results of the study exhibit the change of heating value with variations in adhesive portions. Adhesive of 20% w/w produces the highest heat of 28139,33 calori, second highest is produced from briquettes with 15% w/w adhesive, which is 2713,44 calori and the lowest is from 10% adhesive briquettes with a heating value of 2612,93 calori. The higher portion of adhesive will increase briquette’s heating value because it tighten particles and harden briquettes that extend heat produced. The quality of A, B, C briquettes compared to market briquettes measured by their heating value is market briquettes has much lower heating value than A, B and C which are only 1507,46 calori. &nbsp

Penjerapan Urea dengan Karbon Aktif dari Kayu Bakar

Activated carbon is a universal adsorbent possessing extensive function in human life. Adsorbent has been used in waste effluent treatment to adsorb variety substances mainly in the form of liquid and gas pollutants, odor adsorbent, food preservative, nutrient carrier for plant, and as fuel cell. Adsorbent is become an interest for its highly adsorption capacity due to its abundant pores on its surface resulting wide surface area, its simple manufacturing, its easy finding raw materials-even from waste material, and its relatively low cost of manufacturing. The purpose of this study is to investigate adsorption capacity and urea uptake percentage of activated carbon made from pyrolyzed firewood. The results obtained in this research are activated carbon from pyrolyzed firewood has urea adsorption capacity 0,026 mg urea/g adsorbent at urea concentration of 500 mg/L as high as 479 mg urea/g adsorbent at urea concentration of 50000 mg/L and urea uptake percentage 8,8 % v/v. This result shows that activated carbon from pyrolyzed firewood has capability to adsorb urea molecules form aqueous solution and therefore pyrolyzed firewood can be an alternative of  low cost adsorbent for treating wastewater containing urea

Pengaruh Waktu Karbonisasi Terhadap Kadar Air dan Abu Serta Kemampuan Adsorpsi Arang Tempurung Nipah Teraktivasi Asam Klorida

The Cilacap region, Central Java, Indonesia is a coastal area that is overgrown with nipa palm trees, making it one of the potential local natural resources to be exploited. Utilization of this plant has been carried out for the fields of food, energy, clothing, pharmaceuticals, and furniture, but as an anode material for lithium-ion batteries is still being researched. Studies on lithium-ion batteries in Indonesia in particular have not started long ago so that research in this field is still limited and few in number, but the development of lithium-ion batteries has become one of the national research priorities in the field of new and renewable energy sources as stated in the Indonesian national research master plan (RIRN) for the period 2017 – 2045. This study was conducted to examine the potential feasibility of activated charcoal from nipah shells as anode material for lithium-ion batteries. The feasibility test parameters studied in this study include water content, ash content and adsorption capacity stated as iodine and methylene blue number which are the basic characterizations for activated charcoal referring to SNI 06-3730-1995. The nipah shell carbonization process was carried out in the presence of oxygen at an optimized temperature of 210 oC with a 1 hour time interval variation from 3 to 8 hours, followed by an activation process using a strong acid, namely HCl with a concentration of 2 M. The experimental results showed the average value of moisture content, ash content, iodine, and methylene blue number are 12.5%, respectively; 1.75%; 2515.9161 mg/g; and 97%, all of which are above the quality standard values, so the conclusion from this study is that activated charcoal from nipah shell has basic characteristics that have the potential to be further developed, including as raw material for lithium-ion battery anodes

Analisis Porositas, Tekstur, dan Morfologi Karbon Tempurung Nipah Hasil Pirolisis Suhu Tinggi Untuk Anoda Baterai Sekunder

Lithium-ion batteries are the recent main store of electrochemical energy that have been widely used for electronic equipment, electric vehicles, and also renewable energy storage such as wind and solar. Lithium-ion batteries have many electrochemical advantages but lithium availability in nature is reduced very quickly and its distribution is uneven throughout the world. Sodium is attractive as an alternative to lithium insertion for secondary batteries because of its abundant availability and oxidation reduction potential to standard hydrogen electrodes only 0.3 volts higher than lithium. This study aims to synthesize hard carbon from nipah shell biomass using thermal methods of low-temperature pyrolysis (lower than 200 oC) followed by high-temperature pyrolysis (higher than 1000 oC). Characterization is carried out by iodine number analysis to determine porosity and SEM-EDX to determine texture and morphology. The result of the analysis of carbon iodine number is 346.86 mg/g while SEM-EDX analysis showed that carbon has a structure similar to a combination of graphene and nano-tube carbon.Baterai ion litium adalah penyimpan energi elektrokimia yang utama saat ini yang telah digunakan secara luas untuk peralatan elektronik,  kendaraan listrik, dan juga penyimpan energi terbarukan angin dan matahari. Baterai ion litium memiliki banyak keunggulan elektrokimia diantaranya tegangan atau voltase yang tinggi, kerapatan energi yang tinggi, daya spesifik yang tinggi, memiliki suhu operasi yang lebar, dan ketahanan simpan muatan listrik yang baik, tetapi kelemahannya yakni ketersediaan litium di alam yang berkurang dengan sangat cepat serta distribusinya yang tidak merata di seluruh dunia. Sodium menarik sebagai alternatif pengganti insersi litium untuk baterai sekunder karena ketersediaannya yang melimpah serta memiliki potensial reduksi oksidasi terhadap elektroda hidrogen standar hanya sebesar 0,3 volt lebih tinggi dari litium. Karbon keras dinilai sebagai material paling sesuai untuk anoda baterai ion sodium. Artikel ini mengetengahkan analisis tekstur dan morfologi dari karbon tempurung nipah yang dipirolisis pada suhu tinggi (> 1000 oC) dan mengkaji kelayakannya sebagai bahan baku anoda baterai ion sodium

Potensi Penerapan Konsep Ekologi Industri Untuk Mengatasi Limbah Peternakan Dan Pertanian Kelompok Tani

The agriculture and livestock sector is the biggest contributor to environmental damage. Where from the total national sources of greenhouse gases, the agricultural sector accounted for 13.6%. From this data, there needs to be an appropriate design to deal with this problem. One way is to apply the concept of industrial ecology as the best solution to deal with this problem. So that in this study quantitative calculations were carried out to determine the potential application of the concept of industrial ecology in the agriculture and animal husbandry sector in the Tojang Maju 3 Farmer Group located in Masbagik District, East Lombok Regency, West Nusa Tenggara Province. The study was conducted with a quantitative calculation of waste generated by the livestock sector as well as farmer group questions, which then carried out the design process of the industrial ecological model. The results obtained the use of liquid organic fertilizer (POC) in the agricultural sector as much as 280.5 for rice, 37.4 for chilli farming, and 37.4 liters for cabbage farming and the rest as sources of economics. Whereas straw produced by rice farming (57,000 kg) is used as silage in the livestock sector with a demand of 4,957.2 kg. Rice straw is also used in the chilli agriculture sector as mulch with a requirement of 1,140 kg and the rest (50,903 kg) is used as raw material for the production of synthetic gas for energy sources of farmer groups. While the rest of the chilli and cabbage agricultural products are used as raw material for biogas with a mass of around 70,300 kg which is directly utilized by the groups. For cow as much as 5,355 kg is fed to the biogas digester as biogas for the consumption of farmer groups, with a gas potential of 535.5 m3

Pengaruh Variasi Konsentrasi H3PO4 Sebagai Zat Aktivator Terhadap Karakteristik Karbon Aktif dari Sekam Padi

Rice husk is an organic material that has a high lignocellulosic content so it has the potential to be turned into activated carbon. One method of making activated carbon is activation with a phosphoric acid activator (H3PO4). The purpose of this research was to study the effect of varying concentrations of H3PO4 as an activator on the characteristics of rice husk-activated carbon. The characterization refers to SNI 06-3730-1995 regarding the technical quality requirements of activated charcoal. Activation of rice husk carbon was carried out by contacting the carbon with H3PO4 for 24 hours and shaking it. The H3PO4 consisted of 3 concentration variations, namely 4M, 6M, and 8M. From the research results, the water content was 3.936%; 4.037%; 4.070%, the absorption of iodine has met the character of activated charcoal according to SNI, namely 1217.204 mg/g; 1204.255 mg/g; 1184.832 mg/g while the ash content value does not meet the SNI standard, which is still above 10%. The highest adsorption capacity and adsorption efficiency could be activated with 8M H3PO4, namely 22.42 mg/g and 89.68%. IR spectra on activated carbon with three variations of H3PO4 concentration showed the presence of aromatic C-H, C=C, and C-O anhydride functional groups.Sekam padi merupakan bahan organik yang mempunyai kandungan lignoselulosa yang tinggi sehingga berpotensi untuk dibuat karbon aktif.. Salah satu metode pembuatan karbon aktif adalah aktivasi dengan aktivator  asam phospat (H3PO4). Penelitian ini bertujuan untuk mempelajari pengaruh variasi konsentrasi H3PO4 sebagai aktivator terhadap karakteristik karbon aktif dari sekam padi. Karakterisasi mengacu pada  SNI 06-3730-1995 mengenai persyaratan kualitas teknis arang aktif. Aktivasi karbon sekam padi dilakukan dengan mengkontakkan karbon dengan H3PO4 selama 24 jam sambil dilakukan penggojokan. H3PO4 yang digunakan  terdiri dari 3 variasi konsentrasi  yaitu  4M, 6M dan 8 M . Dari hasil penelitian didapatkan hasil kadar air, daya serap iodine sudah memenuhi karakter arang aktif sesuai SNI sedangkan nilai kadar abu belum memenuhi standar SNI. Sedangkan kapasitas adsorbsi dan efisiensi adsorbsi tertinggi di dapat aktivasi dengan H3PO4 8M. Spektra IR pada karbon aktif dengan ketiga variasi konsentrasi H3PO4 menunjukkan adanya gugus fungsi  C-H aromatik, C=C dan C-O anhidrida

Efek Temperatur Pengarangan Cangkang Kerang dan Tulang Sapi Terhadap Proximate

Studies on the use of animal waste as charcoal ingredient in the needs of activated charcoal material has been carried out and developed. Activated charcoal is produced through activation process at a certain temperature, condition, and time in order to creat a higher carbon content  in charcoal . One of the important factors in the manufacture of activated charcoal is the temperature during the production process. The purpose of this study is to discuss the influence of temperature factor of mussel shells and beef bones on water content, ash content, volatile matter and fixed carbon during the charcoal production process. The research is carried out through experimental method of  making chorcoal with temperature variations of 400, 500, 600, 700, and 800 oC. The result of the experiment shows the highest ash content and water content found respectively in beef bone charcoal of 800 oC which is 98,697 %, and of 400 oC which is 4,942 %, while the highest volatile matter and fixed carbon levels are found in clam shell charcoal of 800 oC which is 6,717 %, and of 500 oC which is 43,282 %. The result concluded that the effect of the temperature of the production process affects the water content, ash, volatile matter and fixed carbon

Pengolahan Limbah Tempurung Kemiri Sebagai Adsorben Senyawa Etilen Dengan Penambahan Kalium Permanganat (KMnO4)

Candlenut (Aleurites mollucana) is one of the biggest potentials, especially in Sumbawa Regency. Apart from being a spice, Candlenut also produces waste in the form of shells with a very large carbon content. So that in this study, the use of candlenut shells as adsorbent was carried out using potassium permanganate or KMnO4. The way it works in this research is by doing a charcoal process on the hazelnut shell waste as the carrying substance. Basically, there are 3 stages in this research, including the carbonization of candlenut shells so that they become charcoal using a drum furnace that has been designed by yourself. Subsequently, the composite beads were sieved by using a 100 mesh sieve. Then KMnO4 is added to the mashed charcoal. The variations in the weight of KMnO4 used are 15 grams, 30 grams, and 45 grams. At the test stage, it was carried out by testing the chemical characteristics of the water content, ash content, and analysis of the best samples. At the end of the study, physical and chemical tests were also carried out on composite beads. The results showed that the best water and ash content was found in the amount of addition of KMnO4 compound at 15 grams, namely 7.33% and 7%, respectively. These results indicate that composite bead products have met the SNI 06–3730-1995 standards. For the effectiveness of absorption of ethylene compounds, the resulting composite beads required 15 grams of KMnO4 for the best absorption of 6.1% ethylene