Pada penelitian ini telah dilakukan sintesis Ion Imprinted Polymer (IIP) logam Fe3+ dengan asam galat sebagai monomer fungsional dan logam Fe3+ sebagai template. Gugus hidroksil (OH) yang terdapat dalam asam galat berperan sebagai donor elektron (ligan) untuk membentuk kompleks dengan template logam Fe3+. Kompleks yang terbentuk dipolimerisasi dengan metode polimerisasi bulk dengan penambahan inisator AIBN dan crosslinker EGDMA. Sintesis IIP dilakukan dengan melakukan variasi perbandingan ligan:monomer (1:1, 1:2, dan 1:3). Hasil sintesis IIP dan NIP (IIP tanpa logam) kemudian dikarakterisasi menggunakan spektrometer Fourier Transform Infra Red (FTIR), Scanning Electron Microscopy (SEM-EDS), dan Thermogravmetric Analysis (TGA). Uji adsorpsi menunjukkan bahwa perbandingan sintesis yang optimum dihasilkan pada rasio perbandingan ligan:monomer 1:2 dengan kapasitas adsorpsi 122,26 mg/g pada pH 5 dan waktu kontak 60 menit. Persamaan regresi dari IIP mengikuti isoterm Freundlich dengan nilai R2 = 0,9789. Uji selektivitas IIP dilakukan terhadap ion logam campuran menunjukkan urutan adsorpsi yaitu Fe(III) > Ag(I) > Cr(III) dengan nilai relatif faktor selektivitas (αr) dari Fe(III) / Cr(II) dan Fe(III)/ Ag (I) masing masing adalah 3,410 dan 0,707. Kemampuan recovery IIP diuji dengan menggunakan sampel air Danau Kenanga UI dan didapatkan persen recovery sebesar 102,02 %, 97,04%, dan 96,61%.
In this study, the synthesis of Fe3+-Ion Imprinted Polymer (IIP) with gallic acid as organic ligand and Fe3+ metal as a template. The hydroxyl (OH) group contained in gallic acid acts as an electron donor (ligand) to form complexes with Fe3+ metal templates. The formed complex then polymerized using bulk polymerization method with the addition of AIBN initiators and EGDMA as crosslinkers. IIP synthesis was carried out by varying the ratio of ligands: monomers (1:1, 1:2, and 1:3). The synthesis results of IIP and NIP characterized using Fourier Transform Infra-Red Spectrometer (FTIR), Scanning Electron Microscopy (SEM-EDS), Thermogravimetric Analysis (TGA). The Fe3+ metal template is leached from the polymer matrix by adding HNO3. Adsorption test exhibit the optimum ratio of 2:1 synthesis with maximum adsorption capacity of 122.264 mg / g at pH 5 with 60 minutes contact time. The adsorption mechanism followed the Freundlich equation with R2 = 0.9789. The IIP selectivity test for adsorption binary metals carried out: Fe (III)> Ag (I)> Fe (Cr) with the relative value of selectivity factor (αr) from Fe (III) / Cr (II) and Fe (III) / Ag ( I) are 3.41 and 0.707, respectively. The recovery test was obtained from water sample with percent recovery 102,02 %, 97,04%, and 96,61%.
Coalbed Methane (CBM) is natural gas with the main content of methane gas that is stored or absorbed into the surface pores of the coal seam matrix. Coalbed Methane (CBM) is one of the potential sources to be used as an alternative energy. Indonesia has quite large CBM reserves of around 453 TCF, which is about 6% of the world's total CBM reserves. Therefore, CBM can be a solution for Indonesia to fulfill national energy needs. However, there are still little information about the adsorption capacity of methane in Indonesian coal, which hampers the development of CBM in Indonesia. Prediction of methane gas adsorption capacity in Indonesian coal in this study using Generalized Ono-Kondo modeling. Generalized Ono-Kondo modeling is one of the adsorption modeling that can be used to predict adsorption capacity, especially for high pressure gas adsorption. The use of modeling in this study includes the calculation of two parameters, namely the value of the interaction energy between the adsorbent and the adsorbate ( ) and the maximum adsorption capacity of the adsorbent (C). In this study, the types of Indonesian coal that will be used are Barito and Ombilin with high pressure above the critical temperature. Based on the simulation results of Ono-Kondo modeling, dry barito coal has a higher maximum adsorption capacity than ombilin coal. The largest adsorption capacity for barito coal is 0.1879 mmol/g and for ombilin coal is 0.16944 mmol/g. The largest adsorption capacity was found in dry barito coal at 30 C with a capacity of 0.1879 mmol/g. The Coal that is not come from Indonesia, namely the Pocahontas and fruitland types, has a higher adsorption capacity than Indonesian coal. Pocahontas coal has a capacity of 0.6479 mmol/g and for fruitland coal is 0.5828 mmol/g. Based on the simulation results, Ono-Kondo modeling can represent methane adsorption on Indonesian coal and coal that is not from Indonesia accurately because it has an AAPD value below 1%.