Papers by Keyword: FTIR

Abstract: This study aimed to determine the characteristics of activated charcoal from mangroves resulting from pyrolysis and activation with 3M KCl using Fourier Transform Infra-Red (FTIR), X-Ray Diffraction (XRD) and ash content analysis and to determine the ratio of Pb, Fe and Cd metal content in river water before and after filtered with activated charcoal. The results of the FTIR test for charcoal from mangroves resulting from pyrolysis and activation with KCl showed the presence of O-H, C=C, C-H, C-N and C-Cl groups as additional groups that appeared after the activation process. The results of XRD analysis show that the lattice parameter (α) can be calculated, namely in pyrolysis mangrove charcoal = 5.79 and charcoal from pyrolysis and activation mangrove wood = 5.88. The results show that there is a change in the distance between the crystal planes after activation, with the known value of, the results of d-spacing 3 strong peaks are 3.39 , 2.94 and 5.88 . The results of the analysis of the ash content are 15.4% and exceed the maximum percentage that has been determined, because there are still impurities attached to the carbon surface. The results of the analysis using Atomic Absorbtion Spectrophotometry (AAS) showed that there were differences in the levels of Pb, Fe and Cd in river water before and after being filtered with activated charcoal. There was a decrease in Pb levels from points 1,2 and 3 as much as 73%, 49% and 55.23%. Meanwhile, Fe metal decreased from points 1, 2 and 3 as much as 58%, 66% and 81%. And on Cd there was a decrease of 44%, 61% and 92%. From these percentage results, activated charcoal from mangroves can be said to be effective because it can absorb metals in river water. Pb metal in river water in East Kombos Manado City has passed the concentration specified in Government Regulation of the Republic of Indonesia No. 22 of 2021, Class II Water Quality Standards.

Abstract: This study aims to produce and characterize CaO (calcium oxide) from limestone, a natural product of Lobong Village. Calcination is the thermal decomposition of limestone to remove carbon so that it can produce calcium oxide. One of the functions of CaO is as an eco-friendly catalyst that does not produce toxic or hazardous waste and can be reused. CaO resulting from the calcination process at a temperature of 900°C for 1.5 h was characterized using XRD, SEM, FTIR, and EDS. XRD analysis of calcined limestone produced 2θ (h k l) diffraction peaks, namely 32.228^o (1 1 1), 37.389^o (2 0 0), 53.864^o (2 2 0), 64.169^o (3 1 1), and 67.404^o (2 2 2) which indicates the dominance of CaO. SEM analysis shows that the morphological structure of Lobong limestone after calcination is more porous than before. Studies by FTIR show that the chemical bonds of carbonate groups in the calcined limestone are decreasing. EDS analysis also shows that the mapping of carbon, which forms carbonates in calcined limestone, is decreasing.

Abstract: In this study, a catalyst based on Montmorillonite clay was implemented for carbon nanotubes (CNTs) synthesizing. The kaolinite clay was used as a supporting material for iron-cobalt bimetallic catalytic nanoparticles. The CNTs have been synthesized by using atmospheric chemical vapor deposition (APCVD). To assess the quality of preparation both the catalyst and CNTs have been characterized by different techniques. The chemical bonding and interactions were verified by FT-IR. The general overview of microstructure was examined using SEM, while, the detailed structure and morphology were examined by HR-TEM, in addition to thermal analysis (DTA); surface area (BET); X-ray fluorescence (XRF), Raman spectroscopy, and XRD analysis. The results revealed that; Fe₂O₃ and Co₃O₄ NPs were uniformly assembled on the clay nanoplatelets. The specific BET surface area of the clay and catalyst was determined to be 46.12 and 57.06 m²/g respectively. Also, from XRD, the peaks at 26° and 42.7° confirm the presence of CNTs. The FTIR absorption bands, D, G, and G^\ bands from the Raman spectrum confirm the hexagonal structure of the CNTs. The obtained results prove the high quality of CNTs preparation.

Abstract: Clinacanthus nutans consists with multiple medicinal properties. The plant is also known to be a source of biologically active compounds, particularly those with an antioxidant capacity. The phytochemical studies of C. nutans plant extract was mostly reported from its leaf part. Thus, the objectives of this study are to assess the phytochemical constituents and antioxidant activity of C. nutans leaf and stem. Methanol was used as solvent for the green extraction. Next, phytochemical screening, Fourier transform infrared (FTIR) analysis, total phenolic (TPC) and flavonoids contents (TFC), quercetin flavonoid compound analysis and in vitro antioxidant activity were performed on C. nutans leaf and stem. In comparison to stem extract, the leaf extract showed a more favorable appearance of metabolites. In FTIR analysis, both sample extracts revealed the presence of hydroxyl and carbonyl functional groups, which are important in antioxidant action. The TPC (228.06 mg GAE/g DW) and TFC (29.76 mg QE/g DW) values were higher in the leaf extract than the stem extract. Quercetin quantification in HPLC analysis revealed that the leaf extract (21.33 g/g) contained more quercetin than the stem extract (18.88 g/g). Between the extracts, leaf providing more antioxidant values of DPPH (15.50%) and FRAP (15.68 gFeSO₄/g) than stem. The greatest association was identified between TFC and FRAP reducing activity (r = 0.977, p<0.05) indicating that the flavonoid present in the extract contributed to C. nutans' antioxidant capacity.

Abstract: Starch-based biodegradable films of polybutylene adipate co-terephthalate (PBAT) have been prepared by the solution casting method. The effect of heating at two different temperatures (80 and 110°C) on the mechanical, optical and morphological properties of these films has been evaluated. The two temperatures were selected based on the crystallization and melting temperatures of PBAT. The blend of PBAT with thermoplastic starch has been prepared by melt mixing technique using two roll mills and then the solution casting method has been followed to prepare the films. Apart from curing at room temperature, the films have been cured at 80°C and 110°C. The tensile strength of the films increased by 110% and 252% for films heated to 80°C and 110°C, respectively. As revealed from spectroscopic analysis, the heating of films has no significant effect on the absorption of light by the films in the UV-visible region. The bonding characteristics of the films have been evaluated using Fourier transform infrared (FTIR) spectroscopy. The lowest water absorption and vapour permeability have been obtained in films cured at 80°C.

Abstract: In this study, silver-silica (Ag/SiO₂) was synthesized using the sol-gel method by silica from rice husks. Silica derived from rice husk waste was previously synthesized using the sol gel method. In addition, the Ag material used in this study was also performed into silver nanoparticles (AgNPs). This method was chosen to obtain an Ag/SiO₂ composite with nano size and high purity. AgNPs were synthesized using silver nitrate (AgNO₃) by reduction method at 90 °C. The reducing agent and stabilizer used is trisodium citrate. UV-Vis, FTIR, XRD, and SEM-EDX were used for the analysis Ag/SiO₂ composites. Uv-Vis analysis results Ag/SiO₂ has an absorption peak at a wavelength of 412 nm with a bandgap energy of 2.25 eV. These peaks indicate that AgNPs have formed in the SiO₂ membrane. The FTIR results revealed the Si-O-Si bonds which indicated the presence of silica and the Ag-O functional group, and the presence of AgNPs. The results of XRD analysis showed that the silica structure formed was cristobalite and silver crystals in the face center cubic (fcc) shape. The results of the SEM-EDX morphological analysis showed that the Ag/SiO₂ nanocomposite was shaped like sharp stone chips and the presence of small granules (granules) with different particle sizes and shapes, slightly porous and the composition of the compounds in the Ag/SiO₂ nanocomposite indicated the presence of various chemical elements in the sample, including carbon, oxygen, sodium, silica, and silver.

Abstract: XRF characterization results showed that coal boiler ash contained SiO2 = 29.3%; Al2O3= 14%; Fe2O3= 30.9%; CaO= 18.3% and palm shell boiler ash containing SiO2 = 48.9%; Fe2O3= 3.42%; CaO= 13.8%. The FTIR test results show that the OH stretching vibration of the SiOH group absorbs in the regions 3676, 3597, 3462, and 3315 cm-1 at the peak of the coal boiler ash spectrum and 3614, 3502, 3365, and 3323 cm-1 at the peak of the palm shell boiler ash spectrum. From the ECC mortar FTIR test results, it can be seen that the functional group changes with the OH stretching vibration of the SiOH group absorbing in the 3387 cm-1 area. The results of the ECC mortar compressive strength test at 28 days increased with the addition of coal boiler ash up to 15% and palm shell boiler ash 10%, so the compressive strength was 59.30 MPa.

Abstract: Oil palm empty fruit bunch fibre (OPEFB) is a waste from palm oil mill. It is rich in useful compound residues such as cellulose and carboxymethylcellulose. The increasing interest in OPEFB as a source of cellulose is due to its low cost, renewable and abundantly available, particularly in the Southeast Asia region. Cellulose extraction is affected by pre-treatment, especially during the bleaching process. Thus, this study aims to analyse the effect of bleaching period and treatment using NaClO₂ on cellulose recovery from OPEFB. Batch process of bleaching was carried out in the ratio of 1:50 of fibres to sodium chlorite (NaClO₂) solution of 0.7%. This was followed by analysis of cellulose morphological using FTIR and SEM analysis. The study found that bleaching duration affects cellulose recovery, with the highest yield of 54% found to be at 3 hours of bleaching duration. The bleaching duration was increased up to 6 hours, but found to yield less cellulose, which indicated that certain duration is suitable to provide a condition for higher cellulose yield.

Abstract: Chitin, as well as its deacetylated variant chitosan, has a wide range of applications in biomedical, agricultural, environmental and food industries. Currently, chitin is commercially produced from crustacean shells rather than fungal or insect sources. In this study, chitin from different lifecycle phases of the black soldier fly (BSF) was extracted and deacetylated into chitosan. Both BSF chitin and chitosan were further subjected to FTIR analysis. The chitin extraction yield % was obtained according to the following order: coccoon>larvae>prepupae. On the other hand, the yield of chemical deacetylation of chitin into chitosan showed a different trend: larvae>prepupae>coccoon. All samples have a deacetylation degree (DD) of more than 90 % except for chitosan from prepupae. FTIR profiles indicated all chitin extracted were in the α-form while the deacetylated chitosan matched closely to the commercially available chitosan. Overall, this study indicated that BSF biomass from different lifecycle phases could be a promising alternative resource for industrial chitin and chitosan production.

Abstract: The objective of the present research is to investigate the degradation phenomenon of Polyvinyl Chloride (PVC) cable jacket exposed under accelerated thermally aged at 100°C for 4 days then irradiated under n’s flux of 1.5x 10¹¹ n’s / cm².sec for 1 hr in PARR-2 reactor at PINSTECH. Thermal, mechanical and chemical etc. properties of degraded cable jacket were studied with respect to fresh sample. It was examined that plasticizer content in PVC matrix started to deplete under the effect of temperature which made the matrix more rigid. In addition, the interaction of radiation with polymeric chains weakens the hydrocarbon bonding. The hydrogen and chlorine ions ejected from PVC molecular chains recombine to form hydrogen chloride (HCl) which induces porosity by creating localized pitting. This phenomenon is known as dehydrochlorination which created scissioning in PVC materials. Hence, due to the synergistic effects of temperature and radiation aging, cracks were observed on the outer surface of cable jacket in 2 years equivalent time. This study concludes that cables having PVC insulation are not suitable for long term exposure (i.e. decades) in thermo-irradiation environment.