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"Meningkatnya kegiatan perindustrian seperti industri pelapisan logam dan industri tekstil diiringi pula dengan peningkatan limbah logam-logam beracun di perairan seperti Cr(VI). Telah banyak metode yang digunakan untuk menanggulangi limbah Cr(VI) tersebut, salah satunya dengan metode adsorpsi.Pada penelitian ini, adsorpsi dilakukan dengan menggunakan adsorben gibsit dan gibsit terinterkalasi litium. Metode purifikasi yang digunakan adalah metode Tributh Lagaly yang memberikan pengaruh pada hasil adsorpsi.Adsorpsi dilakukan pada tiga variasi pH yaitu, pH 4, pH 8, dan pH 10. Hasil kapasitas adsorpsi maksimum didapat pada gibsit alam terinterkalasi litium (LiG alam) dengan kondisi asam yaitu pH 4 sebesar 7,0662 mg Cr(VI)/g gibsit pada 100ppm. LiG purifikasi memberikan hasil adsorpsi yang lebih rendah, karena banyak unsur-unsur yang hilang, seperti Mg dan Ca yang hilang pada saat proses purifikasi, unsur-unsur tersebut dapat membantu pengurangan jumlah Cr(VI) dengan membentuk ikatan ionik dengan Cr2O7 2- atau CrO4 2-. Proses adsorpsi ini terjadi dengan mekanisme pertukaran anion.

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The advance of industrya ctivities such as metal plating industry and textile industry waste water is followed by an increase in toxic metals in water such as Cr ( VI ). There have been many methods used to combat the waste of Cr ( VI ), the one with the adsorption method. In this study, adsorption performed using adsorbents gibsit and gibsit intercalated lithium. Purification method used is the Tributh Lagaly method which give effect to the adsorption results. Adsorption is done in three variations, namely pH, pH 4, pH 8, and pH 10.

Results obtained at the maximum adsorption capacity of natural gibsit intercalated lithium ( natural LIG ) with a pH that is acidic condition 4 of 7.0662 mg Cr ( VI ) / g gibsit at 100ppm. Lig adsorption purification gave lower results, because many elements are lost during the purification process, the elements can help reduce the amount of Cr ( VI ) to form ionic bonds with Cr2O7 2-or CrO4 2-. The adsorption process occurs with the anion exchange mechanism."

" Low linear density polyethylene/organo-montmorillonite (LLDPE/OMMT) nanocomposites at 1–5 wt% OMMT loading were prepared by the melt intercalation technique. The OMMT was synthesized via an ion exchange reaction by replacing the interlayer of sodium ions (Na+ ) in the repeating unit of silicate layers of montmorillonite (MMT) with the cationic surfactant in the form of trihexyltetradecylphosphonium (THTDP) ions. The obtained OMMT and its nanocomposites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and elemental and thermogravimetric analyses. The interlayer spacing of MMT expanded from 1.41 to 2.29 nm due to the accommodation of THTDP ions in the intergallery of OMMT. The introduction of THTDP in the interlayer of OMMT rendered better dispersion of OMMT layers in the LLDPE/OMMT nanocomposites and significantly improved the thermal degradation properties of nanocomposites as compared to the pristine LLDPE."

"Nanocomposites of zinc-aluminium-anthranilate (ZAAN) have been synthesized at different concentrations of anthranilic acid by co-precipitation method. These materials have been examined in detail by powder X-ray powder diffraction (PXRD) which showed the expansion of the basal spacing from 0.89 to ca. 1.33 nm and the shifting of the 003 peak towards the lower 2q angle. This indicates that the anthranilate anion was successfully intercalated into the interlayer gallery. However, FTIR analysis showed nitrate anion was also co-intercalated in the interlayer. The resulting nanocomposites show Type IV adsorption-desorption isotherms indicated the mesoporous structure of the material. BET surface area was found to be slightly different compared to zinc-aluminium-nitrate-layered double hydroxide (ZANO) after the intercalation process took place. Both ZANO and ZAAN have similar surface morphology, namely a flaky-like structure, but they are of different sizes."

"Limbah plastik merupakan salah satu masalah lingkungan terbesar saat ini. Ini dikarenakan oleh penggunaan plastik konvensional yang berasal dari polimer sintetis yang sulit diuraikan oleh pengurai. Bioplastik menjadi salah satu solusi masalah ini. Pati merupakan polimer alami yang dapat digunakan untuk produksi bioplastik karena sumbernya melimpah, dapat diperbaharui, mudah terdegradasi, dan harga terjangkau. Namun, pati mempunyai kelemahan, yaitu sifat mekanik yang buruk. Partikel penguat telah terbukti dapat memperbaiki kelemahan pati. Penelitian ini bertujuan untuk mendapatkan konsentrasi terbaik ZnO dan selulosa sebagai penguat pada matriks pati. Pembuatan bioplastik dilakukan dengan metode melt intercalation, yaitu pencampuran pati ubi jalar, gliserol, ZnO/selulosa. Penambahan konsentrasi ZnO 0, 1, 3, 6, 9% wt dan penambahan konsentrasi selulosa 0, 1, 3, 6, 9% wt berturut-turut menyebabkan peningkatan kuat tarik dari 12,812 kgf/cm2 menjadi 64,187 kgf/cm2 dan 12,812 kgf/cm2 menjadi 59,740 kgf/cm2, serta penurunan elongasi dari 43% menjadi 6% dan 43% menjadi 6,667%. Sedangkan kombinasi selulosa dan ZnO menyebabkan nilai kuat tarik dibawah 64,187 kgf/cm2. Penambahan ZnO dan selulosa juga terbukti mempengaruhi hasil FT-IR, XRD, dan SEM bioplastik. Hasil WVTR bioplastik dengan penguat 9% wt selulosa adalah 10,097 g/m2.jam. Selain itu, tingkat biodegradabilitas bioplastik dengan penguat alami selulosa mempunyai hasil lebih baik dibandingkan dengan penguat logam ZnO.

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Nowadays, plastic waste is the biggest environmental issues. Since the usage of conventional plastic which come from synthesis polymer that can not be decomposed by decomposers. One of the solutions is bioplastic. Starch is natural polymer that used to produce bioplastic because it is abundant, reneweble, degradable, and affordable resources. However, starch has some weakness such as poor mechanical properties. Reinforcement is proven to enhance that weaknesses.

This research objective is to obtain the best ZnO and cellulose concentration as reinforcement for starch matrix. Bioplastic synthesis made with melt intercalation method, which is blending from sweetpotato strach, glycerol, ZnO/cellulose. The addition of ZnO concentration 0, 1, 3, 6, 9 wt% and cellulose concentrarion 0, 1, 3, 6, 9 wt%, respectively will cause increasing in tensile strength from 12.812 kgf/cm2 become 64.187 kgf/cm2 and 12.812 kgf/cm2 become 59.740 kgf/cm2, decreasing in elongation from 43% become 6% and 43% become 6.667%. While the combination of cellulose and ZnO causes tensile strength values below 64.187 kgf/cm2. It is also proven by the addition of ZnO and cellulose affect the result of bioplastic FT-IR, XRD, and SEM.

The result of bioplastic WVTR with 9 wt% cellulose reonforcement is 10.097 g/m2.jam. Moreover, the level of bioplastic biodegradability with celluloce natural reinforcement is better than ZnO metal reinforcement."

"Penelitian ini dilakukan untuk proses modifikasi bentonit alam Tapanuli menjadi organobentonit dengan cara menginterkalasi bentonit menggunakan monosodium glutamat yang berasal dari penyedap masakan. Peningkatan kandungan montmorillonit dilakukan dengan proses fraksinasi-sedimentasi pada suspensi bentonit. Monmorillonit yang diperoleh, diseragamkan kation penyeimbangnya dengan ion Na+ menjadi Na-Bentonit. Selanjutnya penentuan nilai Kapasitas Tukar Kation (KTK) dilakukan dengan menggunakan metode memakai senyawa kompleks [Cu(en)22+], dan diperoleh nilai KTK sebesar 46,74 mek/100g bentonit. Sintesis organobentonit dilakukan dengan menambahkan larutan monosodium glutamat pada pH 3,22 yaitu pH pada titik isoelektrik asam glutamat agar terbentuk muatan positif pada gugus amina monosodium glutamat (-NH3+), yang dapat berinteraksi dengan muatan negatif pada permukaan antarlapis bentonit. Hasil proses interkalasi diuji dengan menggunakan XRD dan FTIR. Organobentonit yang diperoleh diaplikasikan untuk adsorpsi logam berat ion kadmium dan timbal. Hasilnya menunjukkan bahwa walaupun tidak terjadi perbedaan yang signifikan, organobentonit 2 KTK memiliki daya adsorpsi lebih baik dibandingkan dengan 1 KTK dan bentonit alam. Adsorpsi terhadap ion Pb relatif lebih baik daripada ion Cd.

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This study is to intercalate a Natural clay of Tapanuli using monosodium glutamate sourced from food flavoring. Prior to intercalation of bentonit, the clay was purified through a sedimentation process in order to obtain clay with high content of montmorilonite. The cation on the monmorillonite fraction then was converted into Na-Monmorillonite by adding NaCl solution. Furthermore, the Cation Exchange Capacity (CEC) of Na-Monmorillonite was determined using [Cu(en)22+] complex, and was obtained to be 46.74 meq/100g.

Organoclay synthesis was prepared by adding equivalent amount of monosodium glutamate solution at the isoelectric point of glutamate acid at pH 3.22. The isoeletric point was choosen in order to form a positive charge on monosodium glutamate (-NH3+) that can interact with negative charge on the surface of the clay interlayer. The presence of intercalated glutamate in the bentonite interlayer was performed using XRD and FTIR spectrometry. The intercalated bentonite (organoclay) was applied to absorb cadmium and lead ions.

The result showed that the organoclay 2 CEC has the better adsorption capacity compared to the 1 CEC and natural clay eventhough not different significantly. Clay absorption capacity of cadmium and lead ions are not much different, but the organobentonite the absorption capacity of lead is higher than the absorption capacity of cadmium."

"Bentonit alam Jambi telah berhasil dimodifikasi menjadi Organoclay melalui proses interkalasi dengan senyawa asam amino Alanin. Sebelum dilakukan sintesis Organoclay, dilakukan proses fraksinasi dan sedimentasi dari bentonit alam Jambi yang bertujuan untuk mendapatkan bentonit yang kaya akan montmorillonite (MMT) dan menghilangkan pengotor yang terkandung di dalam bentonit. Kemudian dilakukan penyeragaman kation bebasnya dengan Na+ menjadi Na- Bentonit. Selanjutnya dengan menggunakan larutan tembaga amin, dilakukan penghitungan nilai Kapasitas Tukar Kation (KTK) dan diperoleh nilai KTK sebesar 35,3 mek/100 gram bentonit. Sintesis Organoclay kemudian dilakukan dengan menginterkalasikan senyawa Alanin ke dalam Na- MMT dengan 2 nilai KTK pada 3 kondisi pH, yaitu pH 4,7, pH isoelektrik Alanin (pH 6), dan pH 7. Hasil dari karakterisasi FTIR menunjukkan bahwa senyawa asam amino Alanin telah berhasil diinterkalasi ke dalam bentonit alam Jambi pada pH isoelektrik dengan munculnya serapan baru pada bilangan gelombang yang berbeda dengan Na- MMT. Organoclay yang telah disintesis kemudian digunakan sebagai adsorben ion logam berat kadmium dan timbal dengan proses optimasi waktu dan konsentrasi adsorpsi. Hasil menunjukkan bahwa Organoclay memiliki daya adsorpsi yang lebih besar terhadap logam berat dibandingkan dengan bentonit alam. Variasi pH interkalasi 4,7 dan 7 menghasilkan Organoclay dengan kemampuan adsorpsi yang lebih rendah dibandingkan Organoclay yang di interkalasi pada pH isoelektrik Alanin.

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Natural Jambi bentonite have been successfully modified into Organoclay through the intercalation process with acid amino compound Alanine. Before the process for the synthesis of Organoclay begins, the process of sedimentation and fractionation conducted on natural Jambi bentonite in order to get the rich inmontmorillonite (MMT) bentonite and removed the contaminer contained in the bentonite. Then the equalization of free cations is done with Na+ (called Nabentonite). Next, using a solution of copper amine, its cation exchange capacity (CEC) determined and the value of CEC acquired was 35,3 meq/100 grams of bentonite. Synthesis of Organoclay then performed by intercalating Alanine into Na-MMT with 2 values of CEC on 3 pH conditions i.e. pH 4,7, the isoelectric pH of Alanine (pH 6), and the pH 7.

The results of the characterization with FTIR indicated that acid amino Alanine compounds has managed to be intercalated into natural Jambi bentonite with the appearance of new absorbance at different wave number from Na- MMT. Organoclay which have been synthesized then used as an adsorbent of heavy metal ions cadmium and lead with the optimization of adsorption time and concentration process.

The results show that Organoclay have better adsorption capacity compared to unmodified natural Jambi bentonite against heavy metal ions. Organoclay synthesized in variated pH conditions (4,7 dan 7) have lower adsorption capacity than the Organoclay that synthesized in isoelectric pH of Alanine."

"Material berlapis, seperti logam dikalkogenida tin disulfida (SnS2), merupakan material menjanjikan untuk penyimpanan ion Na pada anoda baterai natrium. Struktur yang dimiliki SnS2 memberikan peluang untuk mengatur jarak antarlapisan agar semakin banyak ion Na yang dapat ditampung sekaligus meningkatkan laju difusi ion Na dalam material tersebut. Penelitian ini menggunakan density functional theory (DFT) untuk mempelajari pengaruh jarak antarlapisan terhadap energi ikat pada proses interkalasi ion Na. Selain itu, penelitian ini juga mempelajari jalur difusi yang mungkin dilalui ion Na dalam SnS2 serta energi barrier dari setiap jalur menggunakan metode nudged elastic band (NEB). Hasil menunjukkan bahwa ekspansi jarak antarlapisan dapat meningkatkan kinetika interkalasi dan menurunkan energi barrier untuk difusi ion Na yang menjadi kendala utama pada kinerja baterai natrium. Studi ini memberikan gambaran interkalasi dan difusivitas ion untuk desain anoda dalam material berlapis.

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Tin disulfide (SnS2) as layered metal dichalcogenide is a promising material for Na-ion storage as sodium battery anodes. The structure of SnS2 allows controlling the interlayer spacing to accommodate more Na-ion and increase the diffusion rate of Na-ion in materials. This research used a density functional theory (DFT) to study the effect of interlayer spacing on the binding energy of the Na ion intercalation process. In addition, this study observed the possible diffusion pathway for Na-ion in SnS2 and the barrier energy of each pathway using the nudged elastic band (NEB) method. The result shows that interlayer expansion can improve intercalation kinetics and decrease the barrier energy of Na ion diffusion which is the main constraint on sodium batteries’ performance. This study provides an overview of ion intercalation and diffusion for anode application in layered materials."