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"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."

"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."

"Permasalahan pencemaran air oleh ion logam berat memberikan pengaruh sangat buruk bagi kehidupan dan lingkungan karena sifatnya yang non-biodegradabel. Adsorpsi merupakan metode yang sangat efisien dan murah untuk menghilangkan polutan ion logam berat dari air limbah. Dalam penelitian ini, dilakukan studi adsorpsi ion logam Pb(II) dan Cd(II) menggunakan hidrogel berbasis PAA yang dimodifikasi oleh kitosan. Pembentukan hidrogel poli(asam akrilat)-kitosan (PAA-CTS) dilakukan dengan metode iradiasi gamma melalui reaksi polimerisasi radikal bebas dan dikarakterisasi menggunakan spektroskopi FTIR. Dilakukan variasi pH, konsentrasi awal ion logam dan waktu kontak untuk menentukan kondisi optimum dari adsorpsi ion logam Pb(II) oleh hidrogel PAA-CTS. Kondisi optimum adsorpsi ion logam Pb(II) diperoleh pada pH 5,5, konsentrasi awal Pb(II) sebesar 939 ppm dan waktu kontak selama 60 menit. Proses adsorpsi dari ion logam Pb(II) oleh hidrogel PAA-CTS mengikuti isoterm adsorpsi Langmuir dan kinetika adsorpsi orde dua semu dengan konstanta laju, k2, sebesar 1,129x101g/mmol menit. Studi termodinamika menunjukan reaksi yang terjadi selama proses adsorpsi ion logam Pb(II) oleh hidrogel PAA-CTS berlangsung spontan dengan nilai ∆G negatif, ∆H sebesar -88,292 kJ/mol dan ∆S -270,69 J/K mol.

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The problems of water pollution by heavy metal ions have very bad influence for the living and the environment because it’s non-biodegradability. Adsorption is the most efficient and inexpensive method for recovery of heavy metal ions pollutans from wastewater. In this research, conducted studies of Pb(II) and Cd(II) metal ions adsorption using hydrogel based on poly(acrylic acid) (PAA) which modified by chitosan (CTS). Synthesis of poly(acrylic acid)-chitosan (PAA-CTS) was made by gamma irradiation method with free radical polymerization and characterized by FTIR spectroscopy. Do variations of pH, initial concentration of metal ion and contact time for determine optimum conditions from Pb(II) metal ion adsorption by PAA-CTS hydrogel.

The optimum conditions for metal ion adsorption of Pb(II) obtained at pH 5,5, initial concentration 939 ppm of Pb(II) and contact time for 60 minutes. Adsorption process of Pb(II) metal ion by PAA- CTS hydrogel followed by Langmuir adsorption isotherm and pseudo second order kinetics with rate constants 1,129x10-1 g/mmole min. Thermodynamics studies showed that adsorption process of Pb(II) metal ion by PAA-CTS hydrogel was spontaneously with negative value of ∆G, ∆H -88,292 kJ/mole and ∆S -270,69 J/K mole."

"Sintesis zeolit NaY dari zeolit alam Bayat dilakukan melalui metode hidrotermal dengan teknik seeding. Sintesis dilakukan berdasarkan komposisi Al2O3: 10 SiO2: 10,3 Na2O: 180,3 H2O rasio molar . Sebelum dilakukan sintesis, zeolit alam Bayat dipreparasi melalui proses purifikasi dan depolimerisasi. Hasil XRD menunjukkan bahwa zeolit yang dihasilkan merupakan zeolit NaY yang didominasi oleh kerangka sodalite. Hasil SEM-EDX memperlihatkan morfologi zeolit NaY seperti tumpang tindih dengan rasio Si/Al sebesar 2,30. Berdasarkan penelitian, zeolit NaY hasil sintesis memiliki sisi aktif yang besar sehingga dapat berperan menjadi adsorben ion logam kadmium II dan kobalt II. Hal ini dibuktikan dengan kapasitas adsorpsi ion kadmium II rata-rata zeolit NaY hasil sintesis lebih tinggi daripada kapasitas rata-rata adsorpsi dari zeolit alam Bayat raw pada waktu optimum 120 menit, 33,46 mek/100 g untuk zeolit alam Bayat raw dan 105,60 mek/100 g untuk zeolit NaY hasil sintesis. Kapasitas adsorpsi ion kobalt II rata-rata zeolit NaY hasil sintesis juga lebih tinggi daripada kapasitas rata-rata adsorpsi dari zeolit alam Bayat raw pada waktu optimum 120 menit, 12,88 mek/100 g untuk zeolit alam Bayat raw dan 78,25 mek/100 g untuk zeolit NaY hasil sintesis. Nilai kapasitas tukar kation zeolit alam Bayat raw adalah sebesar 24,41 mek/100 gram zeolit, sedangkan nilai kapasitas tukar kation zeolit NaY hasil sintesis adalah sebesar 43,45 mek/100 gram zeolit.

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NaY zeolite was hydrothermally synthesized using seeding technique. The synthesis were performed according to the following composition of Al2O3 10 SiO2 10.3 Na2O 180.3 H2O molar ratio . XRD pattern confirmed that the structure was NaY zeolite. Before synthesis, natural zeolite Bayat were prepared through purification and depolymerization. From XRD measurement, it is observed that zeolite structures are dominated by sodalite framework. SEM EDX showed that NaY crystals were intergrowth with Si Al ratio of 2.30. In this study, NaY zeolite synthesized has more active sites to adsorb cadmium II and cobalt II ions because the average adsorption capacity cadmium II ions of as synthesized NaY zeolite is higher than the average adsorption capacity of raw Bayat natural zeolite at its optimum contact time 120 minutes, 33.46 meq 100 g for raw natural zeolite Bayat and 105.60 meq 100 g for as synthesized NaY zeolite. The average adsorption capacity cobalt II ions of as synthesized NaY zeolite is also higher than the average adsorption capacity of raw Bayat natural zeolite at its optimum contact time 120 minutes, 12.88 meq 100 g for raw natural zeolite Bayat and 78.25 meq 100 g for as synthesized NaY zeolite. The cation exchange capacity of raw Bayat natural zeolite is 24.41 meq 100 gram zeolite, besides the cation exchange capacity of as synthesized NaY zeolite is 43.45 meq 100 gram zeolite. "

"ABSTRAKDalam penelitian ini, MOF disintesis sebagai adsorben ion logam kadmium (II) karena kerangka organik logam (MOF) memiliki area pori dan permukaan yang besar serta sifat potensial dan aplikasi seperti pengolahan air yang mengandung ion logam berat. Sintesis MOF dilakukan berdasarkan logam lantanida menggunakan lantanum dan itrium, dengan mereaksikan logam nitrat (Y (NO3) 3.6H2O dan La (NO3) 3.6H2O) dengan asam suksinat dan N, N-dimethylformamide (DMF) dan pelarut air menggunakan metode solvothermal. Dua MOF yang disintesis dikarakterisasi menggunakan FTIR, XRD, TGA, BET dan SEM. Hasil dari karakterisasi menyatakan bahwa La-succinate MOF lebih baik daripada MO-succinate Y. Selanjutnya, dua MOF yang disintesis digunakan sebagai adsorben ion logam kadmium (II) dengan berbagai variasi seperti pH, waktu kontak, jumlah adsorben dan konsentrasi adsorbat. Kapasitas adsorpsi yang dihasilkan oleh La-succinate MOF lebih besar dari Y-succinate MOF serta hasil dari isoterm adsorpsi oleh La-succinate dan MOF-succinate Y. La-succinate MOF memiliki R2 sebesar 0,9946 dengan nilai kapasitas adsorpsi Freundlich sebesar 2.296 mg / g dan MO-succinate Y memiliki R2 sebesar 0.8812 dengan nilai kapasitas adsorpsi Freundlich sebesar 1.543 mg / g.

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ABSTRACTIn this research, MOF was synthesized as cadmium (II) metal ion adsorbent because the organic metal framework (MOF) has a large pore and surface area as well as potential properties and applications such as water treatment containing heavy metal ions. MOF synthesis was carried out based on lanthanide metal using lanthanum and yttrium, by reacting metal nitrate (Y (NO3) 3.6H2O and La (NO3) 3.6H2O) with succinic acid and N, N-dimethylformamide (DMF) and water solvents using the solvothermal method. Two MOF synthesized were characterized using FTIR, XRD, TGA, BET and SEM. The results of the characterization stated that La-succinate MOF was better than MO-succinate Y. Furthermore, two MOF synthesized were used as adsorbent of cadmium (II) metal ions with various variations such as pH, contact time, amount of adsorbent and adsorbate concentration. The adsorption capacity produced by La-succinate MOF is greater than Y-succinate MOF and the results of adsorption isotherms by La-succinate and MOF-succinate Y. La-succinate MOF has an R2 of 0.9946 with a Freundlich adsorption capacity value of 2,296 mg / g and MO-succinate Y has R2 of 0.8812 with a Freundlich adsorption capacity value of 1,543 mg / g."

"Logam berat seperti timbal (Pb) merupakan salah satu unsur jejak (trace element) yang bersifat sangat toksik bahkan pada konsentrasi yang sangat rendah. Aktivitas industri merupakan sumber utama limbah Pb di lingkungan. Maka dari itu diperlukan metode dengan limit deteksi rendah serta selektivitas tinggi untuk meningkatkan efisiensi pemisahan dan analisis Pb dari lingkungan seperti metode prakonsentrasi. Metode prakonsentrasi yang paling umum digunakan adalah Solid-Phase Extraction (SPE). Pada penelitian ini disintesis Pb(II)- ion-imprinted polymer (IIP) untuk meningkatkan selektivitas dan sensitivitas metode ekstraksi fasa padat (II) menggunakan ion Pb2+ sebagai ion template, asam galat sebagai ligan, 4-vinilpiridin sebagai monomer fungsional, AIBN sebagai inisiator, dan EGDMA sebagai agen pengikat silang. Sintesis IIP menggunakan gelombang ultrasound bertujuan untuk meningkatkan efisiensi polimerisasi. NIP sebagai pembanding disintesis dengan metode yang sama, tanpa menggunakan template. Hasil sintesis Pb(II)-IIP dan NIP dikarakterisasi menggunakan FTIR, SEM-EDS, TGA. Pb(II)-IIP 1:1 memiliki kapasitas adsorpsi paling besar yaitu 123,812 mg/g optimum pada pH 6 dan waktu kontak 120 menit. Isoterm adsorpsinya mengikuti isoterm Freundlich dan kinetika adsorpsinya mengikuti persamaan pseudo-orde dua. Parameter validasi linearitas menghasilkan nilai R2 = 0,9882, repeatabilitas dengan nilai RSD 0,086%, selektivitas terhadap logam biner Pb/Fe, Pb/Zn, Pb/Cd, Pb/Cu, dan Pb/Cr menghasilkan nilai α berurutan 16,6; 52,5; 39,2; 18,5; dan 24 yang berarti Pb(II)-IIP selektif terhadap Pb dibanding logam kompetitornya, dan uji rekoveri menunjukan hasil dengan akurasi yang baik dengan nilai persen rekoveri 104,180%; 105,431%; dan 104,262%.

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Lead (Pb) is a heavy metal that is extremely toxic even at low concentrations. Pb waste in the environment comes primarily from industrial activity. To improve the efficiency of the separation and analysis of Pb from the environment, a method with a low detection limit and good selectivity, such as the preconcentration method, is required. Solid-Phase Extraction is the most popular preconcentration technique (SPE). Using Pb2+ ions as template ions, gallic acid as ligand, 4-vinylpyridine as functional monomer, AIBN as an initiator, and EGDMA as a crosslinking agent, a Pb(II)-ion-imprinted polymer (IIP) was synthesized to improve the selectivity and sensitivity of the solid phase (II) extraction method. The goal of ultrasound-assisted IIP synthesis is to improve polymerization efficiency. NIP was synthesized using the same method as NIP, but without the use of a template. FTIR, SEM-EDS, and TGA were used to characterize the results of the Pb(II)-IIP and NIP synthesis. The adsorption capacity of Pb(II)-IIP 1:1 is the highest, with 123.812 mg/g optimal at pH 6 and a contact time of 120 minutes. The Freundlich isotherm is followed by the adsorption isotherm, and the pseudo second order equation is followed by the adsorption kinetics. The linearity validation parameter resulted in the value of R2 = 0.9882, the reliability with the RSD value 0.086%, selectivity to binary metals Pb/Fe, Pb/Zn, Pb/Cd, Pb/Cu, and Pb/Cr resulted in sequential values: 16.6; 52.5; 39.2; 18.5; and 24, which means that Pb(II)-IIP is selective for Pb compared to its competitor metals, and the recovery test shows good accuracy with the percent recovery values of 104,180%; 105,431%; and 104,262%."

"Imprinted polymer untuk ion Pb2+ (Pb-IIP) disintesis melalui proses self assembly antara monomer fungsional 4-vinil piridin dan asam metakrilat serta ion Pb2+ sebagai template. Kompleks template/monomer yang terbentuk dipolimerisasi menggunakan metode polimerisasi suspensi dengan pengikat silang etilen glikol dimetakrilat (EGDMA) dan inisiator 2,2?-azobis isobutironitril (AIBN). Proses leaching menggunakan HNO3 0,5 M dilakukan pada Pb-IIP hasil sintesis untuk mengelusi ion Pb2+, sehingga didapatkan rongga spesifik yang berfungsi sebagai situs pengenalan. Keberhasilan sintesis polimer dianalisis menggunakan FTIR. Puncak gugus C=C ulur vinil pada panjang gelombang 1630 cm-1 tidak muncul menandakan putusnya ikatan rangkap akibat adanya proses polimerisasi. Hasil karakterisasi EDX menunjukkan bahwa pengompleksan dan pengelusian ion Pb2+ berhasil dilakukan yang dikonfirmasi dengan munculnya intensitas Pb sebelum dilakukan elusi dan tidak munculnya intensitas Pb setelah dilakukan elusi. Hasil karakterisasi menggunakan PSA menunjukkan distribusi ukuran partikel Pb-IIP yaitu 34,5μm. Adsorben Pb-IIP diuji sifat adsorpsi serta desorpsinya dan diperoleh persen adsorpsi di atas 99% dan persen desorpsi sebesar 92,45%. Sebagai pembanding, pada non imprinted polymer (NIP) diperoleh persen adsorpsi sebesar 21,63% dan persen desorpsi sebesar 52,57%. Pb-IIP memiliki persen adsorpsi yang lebih besar terhadap Pb2+ dibandingkan dengan ion logam lainnya yaitu Ni2+, Co2+, Cu2+, dan Fe3+. Kemampuan adsorpsi maksimum pada Pb-IIP dapat dicapai saat pH 7 dan waktu kontak 60 menit. Pb-IIP dapat diaplikasikan pada sampel air di lingkungan dengan % recovery sebesar 110%.

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An imprinted polymer for Pb2+ ion (Pb-IIP) was synthesized by self-assembly method using 4-vinyl pyridine, methacrylic acid as functional monomer and Pb2+ ion as template. Template/monomer complex was polymerized using a suspension polymerization method with crosslinker ethylene glycol dimethacrylate (EGDMA) and initiator 2,2'-azobis isobutyronitrile (AIBN). Pb-IIP was leached using 0.5 M HNO3 to remove Pb2+ ion that would produce the specific cavity as a recognition site. The success of synthesis was analyzed using FTIR resulting the absence of peak for C=C stretching at 1630 cm-1 indicated the bond rupture due to the polymerization process.

EDX characterization indicated that complexing and leaching of Pb2+ ion were successfully confirmed by the appearance of Pb elements prior to elution and disappearance of Pb elements after elution. PSA characterization showed the particle size distribution of Pb-IIP was 34.5 μm. Adsorption and desorption process were performed on Pb-IIP adsorbent obtained > 99% for adsorption and 92.45% for desorption. NIP adsorbent used for comparison with Pb-IIP resulting 21.63% for adsorption and 52.57% for desorption. Pb-IIP had a better adsorption towards Pb2+ compared with other metal ions such as Ni2+, Co2+, Cu2+, and Fe3+. The maximum adsorption capacity of Pb-IIP could be achieved when the pH was 7 and contact times was 60 minutes. Pb-IIP could be applied to environmental water samples resulting % recovery 110%."

"[Ligan para-di-2-(1-methyl-3-pyridyl-4,5-dihydro-1H-pyrazol-5-yl)benzena sudah berhasil disintesis melalui metode kondensasi Aldol. Hasil yang diperoleh dikarakterisasi menggunakanspektrofotometer UV-Vis, spektrofotometer inframerah dan spektrometer NMR. Aplikasi ligan ini adalah sebagai Sensor ion logam Pb2+dan dilakukan menggunakan spektrometer UV-Vis. Hasil dari studi sensor menunjukkan bahwa ligan mempunyai intensitas absorbansi yang kuat. Hal ini didukung oleh nilai absorptivitas molar (?) yang besar. Studi spektroskopi UV-Vis pada penambahan ion Pb2+ menunjukkan munculnya puncak baru pada daerah panjang gelombang 290 nm. Hal ini menunjukkan adanya pembentukan kompleks antara ion logam (Pb2+) dengan ligan para-di-2-(1-methyl-3-pyridyl-4,5-dihydro-1H-pyrazol-5-yl)benzena. Studi aplikasi sensor menunjukkan bahwa ligan ini dapat dijadikan sensoruntuk ion Pb2+ karena penambahan ion ini menyebabkan penurunan intensitas serapan absorbansi. Hasil studi efektivitas sensor menunjukkan bahwa ligan para-di-2-(1-methyl-3-pyridyl-4,5-dihydro-1H-pyrazol-5-yl)benzena merupakan sensor yang efektif terhadap penambahan ion Pb2+ pada panjang gelombang maksimum (?maks) 291 nm.

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The Ligand para-di-2-(1-methyl-3-pyridyl-4,5-dihydro-1H-pyrazol-5-yl)benzene has been synthesized well by using Aldol condensation method. The result of synthesizing is characterized byUV-Visible spectrophotometer, Infrared spectrophotometer and NMR spectrometer. The application of this ligand as sensor for Pb2+ metal ions was studied by using UV-Visible spectrophotometer. Sensingstudiesindicatethat theligandhas astrongabsorbans intensity. This is supportedby alarge molarabsorptivity (?) value. UV-Vis spectroscopystudiesonthe addition ofPb2+ ions showedthe emergence ofa newpeakat290nmwavelength region. This indicatesthat thecomplexesformedbetweenmetalions(Pb2+) with para-di-2-(1-methyl-3-pyridyl-4,5-dihydro-1H-pyrazol-5-yl)benzene ligand. Application sensor studies showed that theseligandscanbe used assensorforPb2+ionsdue tothe addition oftheseionscauses a quenched inabsorbans intensity. The results ofthe study ofsensor efectivity showedthattheligandpara-di-2-(1-methyl-3-pyridyl-4,5-dihydro-1H-pyrazol-5-yl)benzeneissensorefectiveaddition ofPb2+ionsat themaximumwavelength(?max) 291 nm., 5he 1igand para-di-%-+!-rnethyl-(-pyridyl-*,3-dihydro-!:-pyra