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"The adsorption properties of surface-modified mesoporous silica materials containing ?-cyclodextrin (CD ICS) were studied using two types of gas phase adsorbates (N2 and CH3Cl), along with a dye molecule (p-nitrophenol; PNP) in an aqueous solution. The CD ICS materials possess an ordered silica mesostructure framework that depends on the type of surfactant template and the level of loading of ?-CD. Incremental variations in the uptake of gas phase adsorbates and PNP from an aqueous solution were observed, according to the composition of CD ICS materials. For materials with similar CD loading, the surface area (SA) and pore volume doubled, as the surfactant from dodecylamine to hexadecylamine was varied. The SA of the CD ICS materials decreased by ca. 1.5-fold as the CD loading varied from 2% to 6%. The sorption capacity (Qe; mmol/g) of PNP increased from 61% to 84% as the CD loading increased from 2% to 6% and as the alkyl chain length of the surfactant template varied from C12 to C16. The adsorption properties of CD ICS materials with CH3Cl in the gas phase and for PNP in aqueous solution adopt a multi-layer adsorption profile, as described by the BET isotherm model."

"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."

"Limbah zat warna, khususnya zat warna Methylene Blue (MB) yang biasa digunakan dalam industri tekstil, menjadi permasalahan serius bagi lingkungan karena sifatnya yang sulit terurai dan toksik, merusak estetika dan keseimbangan ekosistem. Hal ini menyebabkan perlunya pengolahan pada limbah zat warna. Penelitian ini fokus pada kondisi optimum pengolahan limbah dengan cara adsorpsi menggunakan Silika Mesopori MCM-41 dan SBA-15 yang berasal dari limbah biomassa Tandan Kosong Kelapa Sawit (TKKS) sebagai adsorben zat warna alternatif yang efisien dan ekonomis. Silika mesopori dipilih karena struktur porinya yang mudah untuk dimodifikasi, dan memiliki kapasitas adsorpsi yang baik karena ukuran porinya. Proses sintesis dimulai dari preparasi SiO2 dari TKKS, diikuti oleh sintesis silika mesopori dengan metode sol-gel dan penggunaan CTAB untuk menghasilkan MCM-41 dan P123 sebagai template untuk menghasilkan SBA-15. Studi ini juga mengkaji kondisi optimum adsorpsi MB dengan variasi konsentrasi adsorbat, suhu, dan waktu, menggunakan metode Box-Behnken. Hasil penelitian ini menunjukkan bahwa TKKS dapat disintesis menjadi material berpori dan dapat digunakan sebagai adsorben metilen biru dengan kondisi optimum pada konsentrasi adsorbat 201,742 ppm, suhu 50°C, dan waktu 15,265 menit. Silika mesopori MCM-41 dan SBA-15 dapat digunakan pada 4 kali siklus pengulangan.

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Waste dye, particularly Methylene Blue (MB) commonly used in the textile industry, poses a serious environmental problem due to its non-biodegradable and toxic nature, harming aesthetics and ecosystem balance. This necessitates the treatment of dye waste. This study focuses on the optimum conditions for treating waste via adsorption using mesoporous silica MCM-41 and SBA-15 derived from oil palm empty fruit bunch (OPEFB) biomass waste as an efficient and economical alternative dye adsorbent. Mesoporous silica was chosen due to its easily modifiable pore structure and good adsorption capacity because of its pore size. The synthesis process began with the preparation of SiO2 from OPEFB, followed by the synthesis of mesoporous silica using the sol-gel method and CTAB to produce MCM-41, and P123 as a template to produce SBA-15. This study also examined the optimum conditions for MB adsorption with variations in adsorbate concentration, temperature, and time, using the Box-Behnken method. The results showed that OPEFB can be synthesized into a porous material and used as a methylene blue adsorbent under optimum conditions at an adsorbate concentration of 201.742 ppm, a temperature of 50°C, and a time of 15.265 minutes. Mesoporous silica MCM-41 and SBA-15 can be used for up to 4 cycles of reuse."

"ABSTRACTPerkembangan sains dan teknologi yang meningkat secara pesat mempengaruhi pertumbuhan ekonomi serta proses industrialisasi. Proses industrialisasi menghasilkan limbah industri yang mengandung logam berat seperti tembaga Cu. Limbah industri dapat menyebabkan pencemaran lingkungan disekitar daerah industri yang ditinggali 15 juta atau 6 dari penduduk Indonesia. Salah satu solusi untuk mengatasi permasalahan tersebut dengan menggunakan material mesopori silika Santa Barbara Amorphous SBA-15 sebagai adsorban. SBA-15 disintesis menggunakan proses sol gel menggunakan Tetraorthosilicate TEOS sebagai prekursor dan Surfaktan Pluronik 123 Triblok Kopolimer sebagai template serta 3-Chloropropyl trimethoxysilane CPTMS sebagai fungsionalisasi agen untuk memodifikasi permukaan SBA-15 agar dapat menjadi adsorban yang baik. Material tersebut dikarakterisasi oleh SAXRD dan TEM untuk mempelajari kristalinitas dan struktur pori material tersebut, FTIR untuk menunjukan kehadiran gugus organik, Brunauer Emmet Teller BET N2 uji adsorpsi isoterm pada 77 K untuk mengetahui luas permukaan pori, serta AAS untuk mengetahui konsentrasi ion setelah proses adsorpsi. Struktur kristal SBA-15 dan SBA-15 CPTMS diketahui adalah 2D heksagonal dengan struktur pori SBA-15 lebih teratur dibanding SBA-15 CPTMS. Luas permukaan SBA-15 CPTMS diketahui lebih rendah dibanding SBA-15, dengan perbandingan 711.061 m2/g dan 831.996 m2/g. Meskipun begitu, pada uji adsorpsi Tembaga, SBA-15 CPTMS memiliki kemampuan adsorpsi yang lebih tinggi.

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ABSTRACTThe high development of science and technology affects the economic growth and industrialization process. The industrialization process produces industrial waste which contain heavy metal such as copper Cu. This industrial waste can harm the environment surronding industrial areas where 15 million or 6 of the Indonesian population live. In order to overcome this problem, mesoporous silica material Santa Barbara Amorphous 15 SBA 15 is used as an adsorbent. SBA 15 was synthesized through sol gel process using tetraorthosilicate as precursor, Pluronic 123 triblock copolymer as template, and 3 chloropropyl trimethoxysilane CPTMS as functionalized agent. CPTMS was used to modify the SBA 15 surface in order to improve the materials as adsorbent. The materials were characterized using SAXRD and TEM to study material rsquo s cristallinity and pore structure, the presence of organic group was examined using FTIR, the surface area of SBA 15 and SBA 15 CPTMS were characterized using Brunauer Emmett Teller BET N2 adsorption isotherm test at 77 K, and the ions concentration in solution after adsorption process was determined using AAS. The crystal structure of SBA 15 and SBA 15 CPTMS was found 2D heksagonal with a more regular SBA 15 pore structure than SBA 15 CPTMS. The surface area of SBA 15 CPTMS was found to be lower than SBA 15, 711.061 m2 g in comparison to 831.996 m2 g. However, in copper adsorption test, it was found that SBA 15 CPTMS has higher adsorption ability."

"ABSTRAKSistem pendingin adsorpsi merupakan salah satu solusi terkait permasalahan lingkungan yang ditimbulkan oleh pendingin konvensional. Walaupun pendingin adsorpsi menghasilkan COP yang rendah dibandingkan dengan pendingin konvensional, berbagai usaha telah dilakukan untuk meningkatkan performa dari sistem pendingin adsorpsi. Penelitian ini bertujuan untuk mengetahui pengaruh dari waktu siklus adsorpsi/desorpsi dan temperatur inlet chilled water pada performa dari chiller adsorpsi dengan dua bed modular adsorber dan menggunakan dua jenis silica gel sebagai adsorben dan air sebagai adsorbate. Chiller diuji pada setting kondisi temperatur hot water inlet dan cooling water inlet sebesar 75-80oC dan 30oC. Waktu siklus adsorpsi/desorpsi dan temperatur inlet chilled water divariasikan untuk mengetahui pengaruhnya terhadap performa chiller adsorpsi dan untuk memperoleh kondisi optimal berkaitan dengan performa. Hasil eksperimen menunjukkan bahwa setting temperatur inlet chilled water yang lebih rendah menghasilkan performa yang lebih baik pada chiller adsorpsi. Nilai Coefficient of Performance COP dan kapasitas pendinginan maksimum diperoleh sebesar 0.59 dan 3.9 pada saat waktu adsorpsi/desorpsi selama 600s dan setting temperatur inlet chilled water 11 oC.

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ABSTRACTcooling system is one solution related to environmental problems caused by conventional cooling system. Although the adsorption cooling produces a low COP compared to conventional cooling, various efforts have been made to improve the performance of the adsorption cooling system. This study aims to determine the effect of adsorption desorption time and chilled water inlet temperature on the performance of the adsorption chiller with two bed modular adsorber and using two types of silica gel as adsorbent and water as adsorbate. Chiller tested on the setting of hot water inlet temperature conditions and cooling water inlet of 75 80oC and 30oC. The adsorption desorption time and chilled water inlet temperature varied to determine the effect on the performance of the adsorption chiller and to obtain optimal conditions with respect to performance. Experimental results show that the lower temperature inlet setting of chilled water resulted better performance of the adsorption chiller. Coefficient of Performance COP value and maximum cooling capacity were obtained at 0.59 and 3.9 at the time of adsorption desorptiom during 600s and chilled water inlet temperature 11 oC. "