This paper shows the using of commercial coconut shell activated carbon (CCS-AC) as an alternative adsorbent for the removal of methylene blue (MB) from aqueous solution. The physicochemical properties of the CCSAC were undertaken using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and pH Point of Zero Charge (pHpzc) method. Batch adsorption experiments were conducted to studThis paper shows the using of commercial coconut shell activated carbon (CCS-AC) as an alternative adsorbent for the removal of methylene blue (MB) from aqueous solution. The physicochemical properties of the CCSAC were undertaken using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and pH Point of Zero Charge (pHpzc) method. Batch adsorption experiments were conducted to study the influence of adsorbent dosage (0.02 – 0.50 g), pH (3 – 10), MB concentration (25 – 400 mgL-1 ) and contact time (0 – 36 hours) on the adsorption of the MB. The kinetic adsorption was well described by the Pseudo Second Order model and the Langmuir model described the adsorption behavior at equilibrium. The maximum adsorption capacity (qmax) of CCS-AC obtained was 149.25 mg/g at 303 K. y the influence of adsorbent dosage (0.02 – 0.50 g), pH (3 – 10), MB concentration (25 – 400 mgL-1 ) and contact time (0 – 36 hours) on the adsorption of the MB. The kinetic adsorption was well described by the Pseudo Second Order model and the Langmuir model described the adsorption behavior at equilibrium. The maximum adsorption capacity (qmax) of CCS-AC obtained was 149.25 mg/g at 303 K.
Various sampling techniques such as hydrodistillation, Soxhlet extraction and solid phase micro extraction (SPME) were used to extract compounds, i.e. the active components attributed to fragrance of C. grandis flowers. Gas chromatograph mass spectrometry was then used to identify and quantify the active components obtained from the techniques. The results thus far showed that, buds and blossoms of this flower which possesses a strong floral-, jasmine- and orange-like aroma contain β-myrcene, limonene, ocimene, linalool and caryophyllene as the major compounds. In hydrodistillation technique the levels of ocimene and linalool detected in blossom were higher than in the bud at 7.37 and 15.93%, respectively, while in the bud, limonene was the highest, i.e. 4.57%. In Soxhlet extraction, however the bud was found to consist of limonene (27.25%), ocimene (5.55%) and linalool (2.97%). The performance of three available SPME fibers was compared to evaluate the recoveries of volatile compounds in C.grandis flowers and 100 μm polydimethylsiloxane was found to be the most effective.
Ceramics powder of BaCe0.54Zr0.36Y0.1O2.95 (BCZY) was synthesized using three different methods namely sol-gel (SG), supercritical fluid (SC) and supercritical fluid assisted sol-gel (SCSG). The respective prepared samples were denoted as S1, S2 and S3. TG thermogram of the dried powders for all samples showed three stages of weight loss. Each stage was corroborated by one or two exothermic peaks as shown in DTG signal. Complete thermal decomposition for all the samples was almost accomplished at 1000°C for about 2 h. At calcination temperature of 1100°C, S1 showed a single-phase of perovskite-type oxides as proven by XRD result. Morphology of the calcined powders by SEM micrograph showed that S1 is in spherical shape, S2 is in cubic structure and S3 has a mixture of spherical and rod-like structure. Therefore, as comparison, SG method gives better characteristics of cerate-zirconate ceramics powder compared to SC and SGSC.