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"Ampas tebu berpotensi besar untuk dimanfaatkan menjadi produk yang bernilai tinggi. Penelitian ini bertujuan untuk menghasilkan biochar dari ampas tebu melalui proses pirolisis dengan impregnasi logam dan proses aktivasi untuk digunakan sebagai bahan elektroda superkapasitor. Logam natrium dan nikel dapat memperbesar luas permukaan dan membentuk pori biochar sehingga dapat menghasilkan kinerja superkapasitor yang baik. Kandungan logam natrium dan nikel divariasikan sebesar 0%, 5%, 10%, suhu pirolisis pada 450 °C, 500 °C, 550 °C, dan suhu aktivasi pada 600°C dan 700°C. Karakterisasi dengan BET untuk mengetahui luas permukaan spesifik dan ukuran pori biochar, SEM untuk mengetahui morfologi biochar, dan band gap energy untuk mengetahui sifat konduktivitas biochar. Uji kinerja superkapasitor dilakukan dengan metode cyclic voltammetry menggunakan elektrolit KOH 3 M untuk mengetahui nilai kapasitansi. Didapatkan bahwa biochar terimpregnasi logam Ni 10% yang dipirolisis pada suhu 550 °C dan diaktivasi pada suhu 700 °C merupakan sampel terbaik untuk digunakan sebagai bahan elektroda superkapasitor yang dilihat dari terksturnya berpori, luas permukaan sebesar 285,202 m2/g, band gap energy sebesar 1 eV, dan diperoleh nilai kapasitansi spesifik sebesar 103,292 F/g yang menunjukkan bahwa biochar dapat digunakan sebagai bahan elektroda superkapasitor.

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Sugarcane bagasse has great potential to be used as a high-value product. This study aims to produce biochar from sugarcane bagasse through a pyrolysis process with metal impregnation and activation process to be used as a supercapacitor electrode material. Sodium and nickel metals can increase the surface area and form biochar pores so that they can produce good supercapacitor performance. The contents of sodium and nickel were varied by 0%, 5%, 10%, pyrolysis temperature at 450°C, 500°C, 550°C, and activation temperature at 600°C and 700°C. Characterization with BET to determine the specific surface area and pore size of biochar, SEM to determine the morphology of biochar, and band gap energy to determine the conductivity properties of biochar. The supercapacitor performance test was carried out using the cyclic voltammetry method using 3 M KOH electrolyte to determine the capacitance value. It was found that 10% Ni metal impregnated biochar which was pyrolyzed at 550 °C and activated at 700 °C was the best sample for use as a supercapacitor electrode material as seen from its porous texture, surface area of 285,202 m2/g, band gap energy of 1 eV, and a specific capacitance value of 103.292 F/g was obtained which indicated that biochar could be used as a supercapacitor electrode material."

"Eutrofikasi air merupakan fenomena penurunan kualitas udara yang timbul akibat adanya ion fosfat yang berlebihan dalam suatu ekosistem perairan. Oleh karena itu, untuk menyerap fosfat dari sistem perairan, diperlukan adsorben yang efisien dan efektif. Untuk tujuan penyerapan fosfat dalam sistem perairan, penelitian ini membandingkan massa tiga komposit adsorben yang terdiri dari Biochar teraktivasi yang berasal dari Tandan Kosong Kelapa Sawit (TKKS) dan MgO:KBc (1:5):MgO:KBc (1: 12.5), dan MgO:KBc (1:20). Setelah perlakuan awal dengan KOH, TKKS disintesis melalui pencampuran yang dimodifikasi. Biochar digunakan dalam komposit dengan MgO. Beberapa parameter digunakan untuk mengevaluasi kapasitas adsorpsi, termasuk variasi bahan, variasi pH, dan durasi kontak. Adsorben MgO:KBc (1:5) menunjukkan efisiensi tertinggi dalam adsorpsi fosfat pada pH 7 dengan waktu kontak optimal empat jam. Kinetika adsorpsi MgO:KBc (1:5) adsorben mengikuti kinetika orde dua semu. Hasil terbaik adsorben MgO:KBc (1:5) dalam mengadsorpsi fosfat adalah nilai kapasitas adsorpsi sebesar 9,3108 mg-P/g dan efisiensi adsorpsi sebesar 99,10%. Perangkat DGT terdiri dari gel pengikat, gel difusi, dan membran filter. Agen pengikat bertanggung jawab untuk menempelkan analit tertentu pada gel pengikat. Senyawa MgO:KBc (1:5) digunakan dalam penelitian ini sebagai bahan pengikat pada proses penyerapan senyawa fosfat. Senyawa MgO:KBc (1:5) disintesis menggunakan teknik modifikasi pencampuran dan selanjutnya dianalisis menggunakan FTIR, XRD, FESEM-EDX, dan BET. Keberhasilan sintesis gel pengikat MgO:KBc (1:5) ditunjukkan oleh kesamaan serapan antara gel difusi dan gel pengikat menggunakan FTIR. Waktu optimal DGT MgO:KBc (1:5) adalah 72 jam, dengan konsentrasi 68319,55 ng. Untuk Ferrihidrit DGT waktu idealnya juga 72 jam dengan konsentrasi 57859,29 ng. Terakhir, pH ideal untuk DGT MgO:KBc (1:5) dan Ferihidrit adalah pH 3, dengan konsentrasi 55354,60 ng.

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Water eutrophication is a phenomenon of decreasing air quality that arises due to the presence of excessive phosphate ions in an aquatic ecosystem. Therefore, to adsorb phosphate from water systems, efficient and effective adsorbents are needed. For the purpose of phosphate adsorption in aquatic systems, this study compared the mass of three adsorbent composites consisting of activated Biochar derived from Empty Fruit Bunches (EFB) and MgO:KBc (1:5):MgO:KBc (1: 12.5), and MgO:KBc (1:20). After pretreatment with KOH, EFB was synthesized via modified mixing. Biochar is used in composites with MgO. Several parameters are used to evaluate adsorption capacity, including material variations, pH variations, and contact duration. The MgO:KBc (1:5) adsorbent showed the highest efficiency in phosphate adsorption at pH 7 with an optimal contact time of four hours. The adsorption kinetics of MgO:KBc (1:5) adsorbent follows pseudo second order kinetics. The best results of the MgO:KBc (1:5) adsorbent in adsorbing phosphate were an adsorption capacity value of 9.3108 mg-P/g and an adsorption efficiency of 99.10%. The DGT device consists of a binding gel, a diffusion gel, and a filter membrane. The binding agent is responsible for attaching a particular analyte to the binding gel. The compound MgO:KBc (1:5) was used in this research as a binding agent in the adsorption process of phosphate compounds. The MgO:KBc (1:5) compound was synthesized using a modified mixing technique and then analyzed using FTIR, XRD, FESEM-EDX, and BET. The successful synthesis of the MgO:KBc (1:5) binding gel was demonstrated by the similarity of adsorption between the diffusion gel and the binding gel using FTIR. The optimal time for DGT MgO:KBc (1:5) is 72 hours, with a concentration of 68319.55 ng. For DGT ferrihydrite, the ideal time is also 72 hours with a concentration of 57859.29 ng. Finally, the ideal pH for DGT MgO:KBc (1:5) and Ferrihydrite is pH 3, with a concentration of 55354.60 ng"

"Eceng gondok sebagai gulma air berkembang dengan sangat pesat dalam perairan tawar. Ia sangat potensial untuk dikembangkan sebagai energi terbarukan. Dengan tingginya kandungan karbon dan lignin, ia dapat dimanfaatkan untuk pembuatan biochar sebagai elektroda superkapasitor. Superkapasitor terdiri atas elektroda, elektrolit berupa KOH, binder berupa PVA, crosslinking agent berupa asam sitrat, dan separator berupa kertas saring. Elektroda dengan impregnasi nikel akan dijadikan sebagai superkapasitor simetris, sedangkan untuk superkapasitor asimetris digunakan hasil impregnasi nikel sebagai anoda dan hasil impregnasi Fe2O3 sebagai katoda. Dalam penelitian ini, digunakan 3 variabel bebas berupa persentase berat impregnasi logam, waktu aktivasi, dan konsentrasi elektrolit. Setelah dirangkai menjadi superkapasitor, hasil sampel dari seluruh variasi diuji dengan multimeter digital untuk mengetahui nilai kapasitansinya. Sampel yang berhasil memperoleh nilai kapasitansi tertinggi (146,72 F/g) adalah sampel 26, yaitu superkapasitor asimetris dengan 15% bahan impregnasi pada setiap sisi elektrodanya, waktu aktivasi selama 90 menit, dan elektrolit KOH sebesar 6 M. Hal tersebut menunjukkan bahwa terdapat efek sinergis dari penggunaan bahan impregnasi yang berbeda pada kedua elektroda, serta terdapat pengaruh dari adanya variasi ketiga variabel bebas tersebut. Hasil SEM EDX menunjukkan permukaan biochar dengan distribusi pori yang banyak. Hasil XRF menunjukkan komposisi biochar dan akurasi proses impregnasi yang baik. Hasil FTIR menunjukkan adanya intensitas gugus fungsional yang lebih tinggi dengan adanya peningkatan persentase bahan impregnasi. Hasil band gap energy menunjukkan sampel 26 memiliki sifat semikonduktor dengan band gap energy sebesar 1,0793 eV. Oleh karena itu, seluruh hasil karakterisasi menunjukkan bahwa biochar eceng gondok hasil pirolisis, impregnasi, dan aktivasi dapat berfungsi sebagai penyimpan energi yang baik.

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Water hyacinth as a water weed grows very rapidly in fresh waters. It has great potential to be developed as renewable energy. With its high carbon and lignin content, it can be used to make biochar as a supercapacitor electrode. The supercapacitor circuit consists of electrodes, KOH electrolyte, PVA as binder, citric acid as crosslinking agent, and filter paper as separator. Electrodes with nickel impregnation will be used as symmetric supercapacitors, while for asymmetric supercapacitors the nickel impregnation is used as anode and Fe2O3 impregnation as cathode. In this research, 3 independent variations were used, including the weight percentage of metal impregnation, activation time, and electrolyte concentration. After being assembled as a supercapacitor, the sample results from all variations were tested with a digital multimeter to determine the capacitance value. The sample with highest capacitance value (146,72 F/g) was sample 26, which was an asymmetric supercapacitor with 15% impregnation material on each side of the electrode, an activation time of 90 minutes, and a KOH electrolyte of 6 M. This shows that there is a synergistic effect from the use of different impregnation materials on both electrodes, and there is an influence from variations in the 3 independent variables. SEM EDX results show the biochar surface with a large distribution of pores. XRF results show the biochar composition and good accuracy of the impregnation process. FTIR results show a higher intensity of functional groups with an increase in the percentage of impregnating material. Band gap energy results show that sample 26 has semiconductor properties with a band gap energy of 1.0793 eV. Therefore, all the characterization results show that water hyacinth biochar resulting from pyrolysis, impregnation, and activation can function as a good energy storage."

"ABSTRAKUndang-undang RI No. 19 tahun 2009, pengesahan konvensi Stockholm tentang bahan pencemar organik yang persisten, dan telah melarang penggunaan kategori insektisida yaitu aldrin, klordan, dieldrin, endrin, heptaklor, heksaklorobenzena, mirex, toxaphene dan poliklorinatbifenil (PCB), serta membatasi penggunaan insektisida diklorodifenildikloroetana (DDT). Faktanya, keberadaan insektisida organoklorin tersebut masih ditemukan di tanah sawah Kabupaten Karawang yaitu aldrin, DDT, endosulfan, endrin, heptaklor dan lindan dengan konsentrasi berkisar antara 1,5 ng/g sampai dengan 5,37 ng/g. Teknologi pengendalian residu pestisida dapat dilakukan melalui ameliorasi secara biologi dengan bioremediasi, secara fisika dengan adsorpsi arang aktif, sedangkan, secara kimia melalui penambahan alum dan lain-lain. Bioaugmentasi adalah introduksi mikroba tertentu pada daerah yang akan diremediasi. Bakteri tempatan potensial pendegradasi heptaklor hasil isolasi adalah Citrobacter sp. Setelah diidentifikasi dengan 16S rRNA, bakteri tersebut adalah Raoultella ornithinolytica B4, bakteri ini golongan Enterobacteriaceae, Gram negatif, dan menghasilkan enzim katalase. Biochar tempurung kelapa (BTK) memiliki sifat adsorben berdasarkan nilai daya serap iod sebesar 570,22 mg/g, luas permukaannya 371,943 m2/g, dan diameter pori 0,4-7,0 mm karena proses karbonasi 300 oC menghasilkan ukuran makropori. Hasil uji adsorpsi BTK 5% (b/b) terhadap heptaklor 2 mg/L secara adsorpsi fisik, terlihat dari persamaan Langmuir memiliki linearitas y=1,704x ? 0,002, kapasitas adsorpsinya 1,704 mg/g, dengan efisiensi adsorpsinya sebesar 75,01%. Proses bioaugmentasi tanah sawah tercemar heptaklor oleh bakteri tempatan Raoultella ornithinolytica B4 dengan bantuan BTK 5%, menghasilkan degradasi heptaklor (Rt 11,31 menit) menjadi 1-hidroksiklordene (Rt 12,38 menit), dengan nilai efisiensi remediasi sebesar 75,38%.

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ABSTRACTThe regulation of Republic of Indonesia No. 19 in 2009, about the ratification of the Stockholm Convention on Persistent Organic Pollutans (POPs), that bann the use of insecticides category, namely aldrin, chlordane, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, toxaphene and polychlorinated biphenyls (PCB), and as well as the restriction use of insecticide dichlorodiphenyldichloroethane (DDT). In fact, the presence of insecticides organochlorine are still found on paddy filed, from nine villages and sub-districts in Karawang contained seven types, they are aldrin, DDT, endosulfan, endrin, heptachlor and lindane concentrations in the district ranges from 0.3 ng/g in up to 5.37 ng/g. Bioaugmentation is the applications of indigenous or allochthonous wide type or genetically modified microorganisms to hazardous waste polluted sites in order to accelerate the removal of undesired compounds. Indigenous Bacteria that is potential to degrade heptachlor is obtained from the isolation of Citrobacter sp and finally identified by 16S rRNA identification technique, that this bacteria is Raoultella ornithinolytica B4 which is classified as a group of bacteria of Enterobacteriaceae, as a Gram-negative, and produce the enzyme catalase. Biochar coconut shell (BCS) as adsorbent was tested for its quality by SNI-06-3730-1995 method. It has a water content of 11.88% (w/w), ash content of 3.32%, an easily evaporated substance content of 13.61%, bounded carbon to 71.20%, and iod number of 570.22 mg/g. The adsorption result of BCS 5% (w/w) to heptachlor was 2 mg/L which was fit with physical adsorption of Langmuir equation with adsorption linearity y = 1,704x - 0,002, adsorption capacity of 1.704 mg / g, so BCS can adsorb heptachlor well. Bioaugmentation using single strain of R. ornithinolytica B4 successful for removal of heptachlor with efficiency was observed in 35 days incubation was 75.38%, and heptachlor (11,31 minute) degraded to 1-hydroxychlordene (12,38 minute). "

"Industri ban menyerap sekitar 80% produksi karet dunia dengan kebutuhan carbon black sebanyak 240.000 ton per tahun. Carbon black (CB) umumnya digunakan sebagai filler karet ban untuk meningkatkan sifat mekanis dan memberikan pigmen warna hitam. Sampai saat ini,70% kebutuhan CB masih diimpor dari China dan India. Lignin TKKS merupakan senyawa aromatik dengan kandungan karbon sebesar 60% yang berpotensi sebagai reinforcing filler karet ban setelah terdekomposisi menjadi biochar. Penelitian ini bertujuan untuk memperoleh karakteristik unsur dan morfologi nano-biochar pada suhu 400, 500, dan 600oC serta memperoleh pengaruh rasio nano-biochar terhadap CB N330 pada sifat mekanis karet ban. Nano-biochar pada setiap suhu dianalisis karakteristik fisika-kimianya. Hasil penelitian menunjukkan yield biochar berkurang seiring dengan meningkatnya suhu pirolisis. Jumlah fixed carbon dan kandungan karbon tertinggi diperoleh pada suhu pirolisis 600oC. Sementara itu, luas permukaan biochar tertinggi diperoleh pada suhu pirolisis 500oC sebesar 86,79 m2/g.  Struktur biochar yang lebih berpori diperoleh pada suhu 600oC. Sifat mekanis karet ban lebih tinggi pada tensile strength, elongation at break, modulus 100%, tear strength, dan hardness diperoleh ketika SBR dicampur dengan filler 25% nano-biochar. Hal ini membuktikan potensi biochar sebagai komplemen karbon CB N330 dalam meningkatkan sifat mekanis karet ban.

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The tire industry absorbs about 80% of the world's rubber production with a carbon black requirement of 240,000 tons per year. Carbon black (CB) is commonly used as a tire rubber filler to improve mechanical properties and provide black pigment. Until now, 70% of CB needs are still imported from China and India. Lignin of TKKS is an aromatic compound with a carbon content of 60% which has the potential as a reinforcing filler for tire rubber after being decomposed into biochar. This study aims to obtain the elemental and morphological characteristics of nano-biochar at temperatures of 400, 500, and 600oC and to obtain the effect of the ratio of nano-biochar to CB N330 on the mechanical properties of tire rubber. Nano-biochar at each temperature was analyzed for its physico-chemical characteristics. The results showed that the biochar yield decreased as the pyrolysis temperature increased. The highest amount of fixed carbon and carbon content was obtained at 600oC pyrolysis temperature. Meanwhile, the highest biochar surface area was obtained at 500oC pyrolysis temperature of 86.79 m2/g.  A more porous biochar structure was obtained at 600°C. Higher mechanical properties of tire rubber in tensile strength, elongation at break, 100% modulus, tear strength, and hardness were obtained when SBR was mixed with 25% nano-biochar filler. This proves the potential of biochar as a complement to CB N330 carbon in improving the mechanical properties of tire rubber."

"Interest in using biomass energy as an alternative to fossil fuels has advanced in recent years. This study aimed to assess the effects of torrefaction on the quality of pyrolysis products. Oil palm biomass, such as empty fruit bunches (EFB), mesocarp fiber (MF) and palm kernel shell (PKS) were either untreated (untorrefied) or torrefied (treated), and subsequently pyrolyzed. The experiment’s conditions for torrefaction were set to be a 220°C temperature, a 10°C/min heating rate, and 30 minutes holding time, and for pyrolysis they were set to a 650°C temperature, 20°C/min heating rate and 2 hours holding time. The nitrogen flow rate of 2L/min was maintained for both experiments. The results revealed that the torrefaction pretreatment improved the heating value of the torrefied biomass to 18–21 MJkg-1 from the previous value of 16–19 MJkg-1 for the untorrefied biomass. During torrefaction, the PKS showed a high solid yield of 95% due to high lignin content. The higher heating value (HHV) of the biochar and bio-oil derived from untorrefied and torrefied biomass were between 26–30 MJkg-1 and 16–17 MJkg-1 for the former, and 28–31 MJkg-1, and 17–20 MJkg-1 for the latter. The maximum HHV of 31.2 MJkg-1 was obtained from torrefied PKS biochar. The pyrolysis of torrefied biomass gave higher quality biochar and bio-oil compared to untorrefied biomass. The bio-oil acquired from the pyrolysis of the torrefied sample is less acidic and has a higher calorific value in comparison with the bio-oil obtained from the untorrefied sample. MF and PKS have demonstrated a superior outcome after torrefaction. In this way, the PKS and MF were identified as better biomass for torrefaction and pyrolysis compared to EFB."

"Fosfor atau yang sering ditemukan dalam bentuk fosfat di lingkungan terutama lingkungan perairan diidentifikasi sebagai kontaminan utama yang menyebabkan ledakan alga dan eutrofikasi. Penyerapan fosfat di lingkungan perairan dilakukan dengan membandingkan kemampuan adsorpsi material cangkang telur (CaO), Biochar (BC), dan CaO/Biochar pada variasi massa 1:1, 1:2 dan 2:1 dari pemanfaatan limbah cangkang telur dan jerami. Masing-masing material disintesis dengan mentode ball milling dan pirolisis. Kapasitas adsorpsi diuji dalam variasi material, variasi waktu kontak, variasi konsentrasi larutan serta variasi pH larutan. Isotherm dan kinetika adsorpsi material sesuai dengan isotherm adsorpsi langmuir dan merupakan kinetika adsorpsi pseudo second order (PSO). Material CaO/Biochar 1:2 menunjukkan kapasitas adsorpsi fosfat tertinggi pada pH 12 dikonsentrasi 15 ppm dengan waktu kontak 24 jam. CaO/Biochar 1:2 diaplikasikan dalam proses penyerapan fosfat menggunakan metode Diffusive Gradient in Thin Film sebagai gel pengikat (binding gel) yang bertindak sebagai adsorben. Teknik DGT merupakan teknik preparasi sampel secara in situ dalam mengidentifikasi keberadaan fosfat yang merupakan spesi labil. Material binding agent, dikarakterisasi menggunakan instrument FTIR, XRD dan BJH-BET. Keberhasilan sintesis binding gel CaO/Biochar 1:2 dan Ferryhydrite ditunjukan dengan munculnya serapan yang sama dengan diffusive gel menggunakan FTIR. Waktu optimal DGT CaO/Biochar dan DGT Ferryhydrite t adalah 24 jam, pada konsentrasi larutan fosfat 10 mg/L untuk DGT CaO/Biochar dan DGT Ferryhydrite dengan nilai pH optimum masing-masing untuk DGT CaO/Biochar adalah 5 dan DGT Ferryhydrite adalah 3. Analisis sampel perairan menggunakan teknik DGT dengan binding gel DGT CaO/Biochar dan DGT Ferryhydrite menunjukan bahwa binding gel DGT CaO/Biochar lebih baik dalam mengadsorpsi fosfat di air danau.

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Phosphorus or which is often found in the form of phosphate in the environment, especially aquatic environments, has been identified as the main contaminant that causes algae blooms and eutrophication. Phosphate absorption in the aquatic environment was carried out by comparing the adsorption capabilities of eggshell (CaO), Biochar (BC) and CaO/Biochar materials at mass variations of 1:1, 1:2 and 2:1 from the use of eggshell and straw waste. Each material was synthesized using ball milling and pyrolysis methods. Adsorption capacity was tested in material variations, contact time variations, solution concentration variations and solution pH variations. The adsorption isotherm and kinetics of the material are in accordance with the Langmuir adsorption isotherm and are pseudo second order (PSO) adsorption kinetics. The CaO/Biochar 1:2 material shows the highest phosphate adsorption capacity at pH 12 at a concentration of 15 ppm with a contact time of 24 hours. CaO/Biochar 1:2 was applied in the phosphate adsorption process using the Diffusive Gradient in Thin Film method as a binding agent which acts as an adsorbent. The DGT technique is an in situ sample preparation technique for identifying the presence of phosphate, which is a labile species. The binding agent material was characterized using FTIR, XRD and BJH-BET instruments. The success of the synthesis of CaO/Biochar 1:2 binding gel and ferrihydrite was demonstrated by the appearance of the same absorption as the diffusive gel using FTIR. The optimal time for DGT CaO/Biochar and DGT Ferrihydrite is 24 hours, at a phosphate solution concentration of 10 mg/L for DGT CaO/Biochar and DGT Ferrihydrite with the respective optimum pH values ​​for DGT CaO/Biochar being 5 and DGT Ferrihydrite being 3. Analysis Water samples using the DGT technique with DGT CaO/Biochar and DGT Ferrihydrite binding gels showed that the DGT CaO/Biochar binding gel was better at adsorbing phosphate in lake water."