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"Organobentonit berhasil dibuat dengan proses interkalasi Na-Bentonit dengan senyawa Alanin. Bentonit yang digunakan berasal dari Tapanuli, Sumatera Utara. Na-Bentonit dibuat dari bentonit hasil sedimentasi untuk memperoleh kandungan montmorillonit yang terdapat pada bentonit. Kemudian dilakukan penyeragaman kation pada interlayer bentonit dengan Na+ menjadi Na-Bentonit.Hasil penentuan nilai Kapasitas Tukar Kation dengan menggunakan [Cu(en)2]2+, diperoleh nilai KTK sebesar 45,336 mek/100 gram bentonit. Preparasi organobentonit menggunakan Na-Bentonit yang terinterkalasi Alanin, jumlah Alanin yang ditambahkan sesuai dengan 1 KTK dan 2 KTK dengan 3 variasi pH yaitu pH isoelektrik Alanin (pH 6,01), pH < pI (pH 5) dan pH > pI (pH 7). Hasil karakterisasi organobentonit menunjukkan senyawa Alanin telah berhasil terinterkalasi ke dalam bentonit dan terjadi perubahan pada d-spacing.Organobentonit diuji kemampuan adsorpsinya terhadap ion logam berat Pb2+ dan Cd2+ dengan variasi konsentrasi antara 0,1 mM sampai 0,5 mM, dan membandingkan hasilnya dengan kemampuan adsorpsi dari bentonit alam. Berdasarkan data yang diperoleh menunjukkan bahwa kemampuan menyerap ion logam berat Pb2+ dan Cd2+, organobentonit tidak jauh berbeda dibandingkan Na-Bentonit.

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Organobentonite was successfully made with the intercalation process of Na-Bentonite with Alanine compound. The bentonite was from Tapanuli, North Sumatera. Na-Bentonite was made of the bentonite that resulted from sedimentation process to obtain montmorillonite content in bentonite. Then, cation uniformity was done on bentonite interlayer with Na+ became Na-Bentonite.

In determining the value of Cation Exchange Capacity (CEC) by using [Cu(en)2]2+, the value of CEC obtained was 45,336 mek/100 gram bentonite. In the preparation of organobentonite using Alanine intercalated Na-Bentonite, the amount of Alanine added is in accordance to 1 CEC dan 2 CEC with 3 pH variation : isoelectric pH in Alanine (pH 6,01), pH < pI (pH 5), and pH > pI (pH 7). Characterization result of organobentonite shows that Alanine compound has successfully been intercalated into the bentonite and there has been a change in dspacing.

Organobentonite has been tested in its adsorption ability towards heavy metal ions Pb2+ and Cd2+ with the concentration variation lying among 0,1 mM until 0,5 mM and its result has also been compared with the adsorption ability of natural bentonite. Based on obtained data, it shows that organobentonite`s adsorption ability toward heavy metal ions Pb2+ and Cd2+ is not significally different than Na-Bentonite`s."

"This paper discusses the preparation, characterization, and the evaluation of adsorption properties of resin poly-tetra-p-allylcalix[4]arene tetra acetic acid from the p-t-butylphenol. The synthesized resins were applied as an adsorbent for Cr(III) and Pb(II) metal ions. The adsorption was conducted in a batch system by investigating the effects of acidity (pH), contact time and initial concentration of a heavy metal solution. The adsorption of Cr(III) and Pb(II) metal ions on the resin had the optimum pH rating in region of 4–6 and reached the equilibrium condition in 40 minutes. The adsorption of Cr(III) and Pb(II) metal ions on the resin follows the Langmuir isothermal pattern with the linearity constant (R2 ) of Cr(III) and Pb(II) adsorption, whose results were 0.9640 and 0.9716, respectively. The adsorption capacity of Cr(III) and Pb(II) metal ions is 323.0 µmole/g and 33.4 µmole/g, while the adsorption energy is 30.4 kJ/mole and 39.7 kJ/mole, respectively. Most parameters in batch systems confirm that resin is a good adsorbent for Cr(III) and Pb(II), though Cr(III) adsorption was more favorable than that of Pb(II). The outstanding adsorption abilities for Cr(III) and Pb(II) metal ions have exhibited good prospects for disposal application of polluted water and environmental protection."

"Senyawa kromium banyak digunakan dalam industri modern. Senyawa tersebut banyak dibuang begitu saja ke lingkungan sekitar. Teknologi membrane lebih efisien dan efektif dari pada metode konvensional untuk pengolahan limbah. Tujuan penelitian adalah membuat membran yang dapat digunakan dalam proses pemisahan Cr(VI). Membran dibuat dari kitosan dan silika sekam padi. Variasi kitosan dan silika sekam padi yang digunakan (g) adalah 2:1 (A1), 2:2 (A2), 3:1 (B1), dan 3:2 (B2). Membran dibuat dengan menggunakan teknik inversa fasa. Dari hasil karakterisasi SEM diketahui bahwa membran B2 mempunyai pori yang paling besar yaitu 2,58μm. Hasil karakterisasi FTIR menunjukkan adanya ikatan silang antara kitosan dengan silika sekam padi dengan munculnya pita serapan Si-O pada bilangan gelombang 1122-980/cm. Membran A1 dengan ukuran pori paling kecil mempunyai nilai rejeksi terhadap Cr(VI) paling besar yaitu 70%. Penelitian menunjukkan bahwa membran komposit-silika sekam padi cukup efektif untuk menyerap logam Cr(VI) dengan kapasitas adsorpsi rata-rata adalah 1665.85 mg/g.

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Chromium compounds are widely used in modern industry. Many of these compounds are dumped into the surrounding environment. Membrane technology is more efficient and effective than conventional methods for waste treatment. The research objective is to make a membrane separation proce ss that can be applied to Cr(VI). Membranes are made from chitosan and silica rice husks. Variations of chitosan and silica rice husk used (g) are 2:1 (A1), 2:2 (A2), 3:1 (B1), and 3:2 (B2). The membrane is made by using an inverted phase technique. Results of SEM characterization of membranes show that B2 has the largest pores at 2.58 μ m. The FTIR characterization results indicate the presence of crosslinking between chitosan with silica rice husk with the appearance of Si-O adsorption band at wavelength 1122-980/cm. A1 membrane, with the smallest pore size has the greatest rejection value towards Cr(VI) which is 70%. Research shows that the composite membrane of silica rice husk is effective enough to adsorb metal Cr(VI) with an average adsorption capacity of 1665.85 mg/g. "

"An adsorbed natural gas storage tank was simulated in this work, with the objective being to predict the filling time, the filling capacity and the storage efficiency. A high-capacity HKUST-1 type metal-organic framework was used as adsorbent. The time-dependent phenomenological model of the adsorbed natural gas storage tank was developed considering mass, momentum and energy transfers. The cylindrical tank was 1.09 m in length with a radius of 0.15 m, and was equipped with an inlet hole for gas inflow. The simulation results show that the temperature increase in the tank due to adsorption heat is very significant. This affects the adsorption ability of the bed inside the tank, so the storage efficiency is consequently low. For the inlet gas flowrate of 50 L/min, the storage efficiency is 38% and increases to only 47% at 5 L/min. Corresponding filling capacities for the two flowrates are not very different, i.e. 89 V(STP)/V and 109 V(STP)/V. However, the difference in the filling times is extremely significant, which are 16 min at 50 L/min and 255 min at 5 L/min."

"Limpasan air hujan di perkotaan memiliki kandungan polutan dan logam berat yang tinggi sehingga perlu dilakukan pemurnian agar sesuai baku mutu sebagai alternatif penyediaan air bersih. Bioretensi merupakan solusi yang dapat dilakukan dengan menggunakan media filter dan tanaman air yang efektif untuk meyisihkan polutan dan logam berat dengan salah satu contohnya yaitu tanaman Canna Indica. Pada penelitian ini dilakukan pengujian untuk menganalisis penyerapan nitrogen dan logam berat pada setiap bagian tanaman dan penyisihan nitrogen dan logam beratnya. Penelitian ini menggunakan objek studi Kota Bekasi dengan menggunakan kondisi tanaman yang berbeda yaitu dengan menanam bagian akar, bagian akar dan batang, dan tanaman utuh yang terdiri dari akar, batang, dan tanaman untuk menguji parameter logam besi, kadmium, dan nitrogen. Hasil yang didapat dari penelitian ini yaitu untuk efisiensi penyisihan besi dapat mencapai hingga 98,59%, kadmium mencapai 89,59%, dan nitrogen mencapai 65,53%. Penyerapan besi paling tinggi pada tanaman yaitu pada bagian akar, untuk kadmium pada bagian batang, dan nitrogen pada bagian daun. Kombinasi antara media filter dan Canna Indica mampu menyisihkan dan menyerap logam besi, kadmium, dan nitrogen.

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Rainwater runoff in urban areas has a high content of pollutants and heavy metals, so it is necessary to carry out purification to conform to quality standards as an alternative to providing clean water. Bioretention is a solution that can be done using filter media and water plants that are effective for removing pollutants and heavy metals with one example being the Canna Indica plant. This study aims to analyze the uptake of nitrogen and heavy metals in each part of the plant and the removal of nitrogen and heavy metals. The sampling is in Bekasi City by using different plant conditions by planting only the roots, roots and stems, and whole plants consisting of roots, stems, and plants to test iron, kadmium, and nitrogen. The results indicated that the bioretention efficiently removed 98.59% of iron (Fe), 89.59% kadmium (Cd), and 65.53% nitrogen (N). The highest absorption of Fe in plants is in the roots, for Cd in the stems, and N in the leaves. The combination of filter media and Canna Indica is able to remove and absorb Fe, Cd, N."

"lake eutrophication (eutrofikasi sungai) menjadi salah satu ancaman bagi lingkungan perairan di seluruh dunia, yang dapat merusak ekosistem perairan dan siklus biogeokimia karbon dan unsur-unsur lainnya. Eutrofikasi dapat memicu ledakan alga biru dan hijau (algal bloom) yang mengakibatkan air menjadi keruh, bau tak sedap akibat penguraian, timbulnya zat toksik dan berbahaya, serta mengurangi oksigen terlarut dalam air yang dapat berdampak pada menurunnya diversitas organisme perairan. Oleh karena itu, penghilangan fosfat dari perairan menjadi suatu hal yang sangat penting untuk mencegahnya yang dapat dilakukan dengan adsorpsi menggunakan adsorben yang selektif terhadap fosfat. Oleh karena itu pada penelitian ini, digunakan adsorben yang memiliki performa adsorpsi yang baik dan selektif terhadap fosfat menggunakan Metal-Organic Framework (MOF) dengan Lanthanum sebagai atom pusat dan asam trimesat sebagai ligan organik. MOF lanthanum dan trimesat (LTA) kemudian dipolimerisasi dengan metode Ion Imprinted Polymer (IIP) untuk menghasilkan adsorben yang lebih selektif terhadp fosfat. Adsorben yang disintesis diuji karakterisasinya menggunakan FT-IR dan XRD lalu dianalisis performa adsorpsinya menggunakan metode kompleks amonium molibdat dengan spektrofotometri UV-Vis. Hasil sintesis IIP MOF-LTA memiliki performa yang cukup baik yaitu dengan kapasitas adsorpsi maksimum pada isoterm langmuir sebesar 60,241 mg/g. Sementara itu, pH optimum yang didapat dari IIP MOF-LTA yaitu pH 2.

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Lake eutrophication is a threat to aquatic environments throughout the world,that can damage aquatic ecosystems and the biogeochemical cycles of carbon and other elements. Eutrophication can trigger an explosion of blue and green algae (algal bloom) which results in the water becoming cloudy, an unpleasant odor due to decomposition, the emergence of toxic and dangerous substances due to the presence of several species of algae such as Anabaena sp., as well as reducing dissolved oxygen in the water which can have an impact on decreasing diversity of aquatic organisms. Therefore, removing phosphate from waters is very important to prevent this, which can be done by adsorption using adsorbents that are selective for phosphate. Therefore, in this research, an adsorbent was used that has good adsorption performance and is selective for phosphate using a Metal-Organic Framework (MOF) with Lanthanum as the central atom and trimesic acid as the organic ligand. The lanthanum and trimesate (LTA) MOFs were then polymerized using the Ion Imprinted Polymer (IIP) method to produce an adsorbent that was more selective towards phosphate. The synthesized IIP MOF-LTA adsorbent was then tested for characterization using FT-IR and its adsorption performance was analyzed using the ammonium molybdate complex method with UV-Vis spectrophotometry. The results of the IIP MOF-LTA synthesis have quite good performance, namely with a maximum adsorption capacity on the Langmuir isotherm of 60.241 mg/g. Meanwhile, the optimum pH obtained from IIP MOF-LTA is pH 2."

"Dewasa ini, adsorben telah banyak dikembangkan untuk mengatasi masalah pencemaran logam berat. Pada penelitian ini dilakukan sintesis adsorben dengan gugus fungsional etilendiamin berbasis selulosa. Monomer Glycidyl Methacrylate (GMA) dicangkokkan melalui metode prairadiasi pada selulosa yang telah diiradiasi menggunakan berkas elektron dengan dosis radiasi 40 kGy. Selulosa tercangkok GMA (SG) dimodifikasi menggunakan Etilendiamin (SG-E) pada kondisi optimum untuk diaplikasikan sebagai adsorben ion logam. Hasil sintesis kopolimer SG-E telah berhasil dikarakterisasi dengan FTIR, TGA dan SEM. Hasil persen pencangkokan SG tertinggi diperoleh dengan nilai 266% dengan konsentrasi GMA optimum sebesar 20%. Kondisi optimum sintesis SG-E yaitu pada suhu 80oC dengan waktu reaksi 5 jam dan konsentrasi EDA 2N. Hasil sintesis SG-E pada kondisi optimum memperoleh nilai persen konversi sebesar 12,41 %. Pada kondisi optimum larutan ion logam dalam proses adsorpsi yaitu pada konsentrasi 15 ppm dengan pH larutan 4 dan waktu kontak 150 menit, memperoleh kapasitas adsorpsi sebesar 3,618 mg/g. Isoterm adsorpsi yang sesuai untuk adsorben SG-E dipelajari dan diperoleh isoterm Langmuir dengan nilai regresi 0,974. Kinetika adsorpsi adsorben SG-E didapatkan mengikuti orde reaksi pertama. Berdasarkan hasil yang diperoleh mengindikasikan bahwa adsorben dengan gugus fungsional etilendiamin meningkatkan penyerapan ion logam Pb.

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Recently, adsorbent has been developed to overcome the problem of heavy metal pollution. In this research, a modified cellulose based adsorbent with ethylenediamine functional group was synthesized. Glycidyl Methacrylate (GMA) monomer was grafted through Pre-Irradiation Method into cellulose which has been irradiated using electron beam with 40 kGy radiation dose. GMA grafted cellulose was modified with ethylenediamine at optimum condition to be applied as a metal ion adsorbent. Synthesized copolymer SG-E was successfully characterized by FTIR, TGA and SEM.

The highest result of grafting percent is 266% with 20% GMA concentration. Optimum conditions of SG-E synthesis are at temperature 80oC for 5 hours reaction time with 2 N EDA concentration. Synthesis SG-E at optimum condition is resulting 12,41 % conversion value. The result of SG-E synthesis at optimum condition is 2,0458 mmol EDA/g. At optimum condition which is 15 ppm initial concentration with pH 4 for 150 minute contact time gain 3,618 mg/g adsorption capacity. Adsorption isotherm have been studied. The result show that adsorption process follows Langmuir Isotherm with regression value 0,974. Adsorption kinetic has been observed to follow first order kinetic. Modification of cellulose grafted GMA with ethylenediamine improves lead metal ion sorption."

"ABSTRAKKapal laut merupakan moda transportasi yang digunakan untuk memfasilitasi 90% perdagangan internasional. Hal tersebut membuat kapal laut berpartisipasi dalam membuang sekitar 120 juta ton gas CO2 ke atmosfer setiap tahunnya (Hydros Foundation). Dalam rangka menanggulangi dan mencegah dampak yang lebih buruk dari terperangkapnya gas CO2 di udara, International Maritime Organization menetapkan peraturan yang menuntut indutri perkapalan untuk mengurangi emisi CO2 di masing-masing kapalnya sebesar 40% di tahun 2030 mendatang. Dalam memenuhi tuntutan ini industri dapat menerapkan teknologi post-combustion adsorption. Teknologi adsorpsi tentunya membutuhkan adsorben yang cocok sesuai dengan fungsi yang diharapkan. Pada penelitian ini fungsi yang diharapkan yaitu menangkap gas CO2 pada gas buang kapal, dengan pengaruh adanya gas N2, mengingat gas N2 mempunyai presentase besar pada gas buang kapal. Salah satu adsorben yang memiliki potensi untuk adsorpsi gas CO2 di gas buang kapal adalah MIL-101 (Cr). Material ini memiliki luas permukaan yang besar, dan diiringi dengan kestabilan kimia dan kestabilan termal yang baik. Pada penelitian ini dilakukan sintesis material MIL-101 (Cr) secara hydrothermal, diikuti dengan proses karakterisasi luas permukaan melalui adsorpsi/desorpsi N2, fourier transform infrared sprectoscopy (FTIR), x-ray diffraction (XRD), thermogravimetric analysis (TGA), dan scanning electron microscopy (SEM). Setelah sintesis dan karakterisasi, dilakukan pengujian kapasitas adsorpsi secara volumetrik, kemudian perhitungan selektivitas menggunakan metode ideal adsorbed solution theory (IAST). Berdasarkan penelitian ini didapatkan hasil selektivitas CO2/N2 sebesar 30,1 untuk suhu 27C dan 9,9 untuk suhu 25C.

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ABSTRACTShipping, or sea freight, is still the most crucial mode of transportation, facilitating 90% of the International trade. With that high percentage, shipping also contributes in accumulating more than 120 million tons of carbon dioxide in the atmosphere each year (Hydros Foundation, 2015). In order to prevent and overcome any worse impact from the heat-trapping gas, International Maritime Organization (IMO) set new rules that require the shipping industry to reduce their ships CO2 emission by 40% in the upcoming 2030. To meet this requirement, post-combustion adsorption technology is an interesting option since this method does not force owner to replace their whole ship system but instead just add some additional equipment. Adsorption method required a suitable adsorbent for each specific purpose. In this research the adsorbent is expected to be able to capture CO2 gasses from a ship exhaust, while considering the effect of N2 gasses that mainly dominate the flue gasses. MIL-101 Cr, a type of metal-organic framework, is one potential adsorbent for the required function. This material has a large surface area, along with a great chemical and thermal stability. In this research writer conducted a hydrothermal synthesize of MIL-101 Cr, followed by material characterization: surface area analysis using N2 adsorption/desorption, fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). After the synthesize and characterization, adsorption measurement is conducted using volumetric method and then the selectivity is calculated using ideal adsorbed solution theory (IAST) method. In this research the CO2/N2 selectivity using MIL-101 Cr reached up to 30,1 in 27C and 9,9 in 25C."