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Precipitated calcium carbonate (PCC) is an innovative product generated from lime that significantly offers various functional characteristics in fulfilling numerous market demand. PCC is produced by hydrating high-calcium quicklime resulting slurry so-called milk-of-lime and reacting the slurry with carbon dioxide (CO2) via carbonation process. The resulting PCC product is extremely white and typically has a uniform narrow particle size distribution. PCC is available in various crystal morphologies and sizes, which can be tailored to optimize performance in a specific application. The final properties of the PCC can be diversified by controlling processing parameters. In this current work, effect of liquid air pressure corresponding to feeding rate on a formation of PCC was investigated. In enhancing the product yield, the quicklime was initially converted into a solution containing calcium ion (Ca2+) using natural promoter agent. Subsequently, CO2 gas was continuously supplied into the Ca-rich ionic solution, thus inducing carbonation reaction to form PCC. This present work showed the carbonation time of producing PCC was effectively reduced as a function of feeding rate from 15 minutes at 10 psi to only 7 minutes at 50 psi. The PCC yield slightly increased from 19 g to 23 g with increasing the feeding rate from 10 psi to 50 psi, respectively. Morphologically, the PCC particles were dominated by rhombohedral structures at various feeding rates with an indication of intergrowth mechanism. This current finding signified the increasing feeding rate offered a significant reduction of PCC production time that might be efficiently applied by the industrial manufacturers.

A new approach of using industrial waste to produce synthetic mineral product was studied in this paper. A synthetic mineral product which is precipitated calcium carbonate (PCC) was synthesized by using ionic sucrose solution method, whereby sucrose solution acts as promoter to increase the production of the PCC. Carbide lime, a waste from acetylene gas industry was used as starting material and first dissolved in the sucrose solution. The concentrations of the sucrose solution were varied from 5to 15 °Brix. The effect of the sucrose solution concentration was studied by using multiple characterization methods such as X-ray diffraction (XRD), X-Ray Florescence (XRF) and field emission scanning electron microscope (FESEM). The XRD and XRF results had proven that the synthesized PCC was calcium carbonate with > 98% purity. The morphologies of the PCC were observed by FESEM in which cubical shape was formed at 5 to 12 °Brix and grain shape at 13 to 15 °Brix. The distribution of the PCC particles was observed to be homogenous. The yield of the PCC increased as the Brix values increased.

The purpose of this study was to prepare biphasic granules containing gypsum and carbonated apatite at low temperatures. The biphasic granules were prepared using dissolution-precipitation technique at three different temperatures 30°C, 40°C and 50°C. Characterization of the biphasic granules was determined by multiple analytical methods such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infra-red (FTIR), and CHN Analysis. The obtained granules were determined by XRD as biphasic granules containing bone apatite and gypsum. The cross-section of biphasic granules was observed by SEM. The formed bone apatite was identified as B-Type carbonated apatite using FTIR The carbonate content in biphasic granules fabricated at 30°C, 40°C and 50°C were recorded by CHN analysis as 5.0 wt%, 6.1 wt% and 6.25 wt%, respectively.

A carbonated apatite (CO3Ap) has a closer chemical composition to the bone mineral which may be suit as an artificial bone substitute. In this study, the fabrication works of biphasic gypsum-carbonated apatite granules has been done through the phase transformation by carbonation and phosphorization of the gypsum granules. Gypsum also known as calcium sulphate dihydrate (CSD) granules was immersed into the 2 M of carbonate and phosphate salt solution at 50 °C and room temperature in variable time. The effect of time on the fabrication of biphasic granules were studied using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier transform infrared (FTIR). The XRD analysis was done to confirm the formation of gypsum and hydroxyapatite phases in the biphasic granules. The FTIR spectroscopy indicated that the formation of carbonate apatite was formed in these biphasic granules. The cross sectional morphology of the biphasic granules was observed using SEM. The compositional elucidation was quantitatively measured by CHN analysis to obtain the contents of CO3.Based on the results obtained, it is observed that the CSD was successfully transformed into carbonated apatite to form biphasic granules and time had influenced on the fabrication of these biphasic.

The aim of this paper was to investigate the effects of cross-linked reaction on physicochemical properties of chitosan film by using genipin as cross-linker agent. Series of chitosan film samples with different amount concentration of genipin loaded (0-3 wt %) were prepared and characterized. The physicochemical properties of films were evaluated by Fourier Transform Infra-red (FTIR), UV-vis spectroscopy, Oxygen Transmission Rate (OTR), Scanning Electron Microscopy (SEM), water vapour and tensile test. The cross-linking reaction had affected on colour changing of chitosan film samples from light yellow to dark blue in line with the increasing of genipin concentration. Thus, UV-vis spectroscopy on the cross-linked samples showed the absorbance value at 600 nm wavelength due to genipin content. FTIR observation on cross-linked film samples showed no characteristic of –OCH3 peak from genipin at 1444 cm-1 which resulted by new covalent bonding occurred between chitosan and genipin. Cross-linking also had increased the oxygen barrier and reduced the water vapor rate through the film. Chitosan film sample with addition of 1 wt% genipin achieved the highest tensile stress average at 49.46 MPa compared to other samples while percent of elongation at break reduced with the increasing of genipin concentration loaded

The aim of this study was to investigate the effects of covalent and ionic cross-linked reactions which were respectively done by using genipin and tripolyphosphate (tpp), on the structure and mechanical properties of chitosan film. Both cross-linked and uncross-linked films were prepared by solution casting method and characterized. FTIR spectra showed no characteristic of –OCH3 peak from genipin at 1444 cm-1 which resulted by a new covalent bonding in chitosan film. Reduction in absorption intensity at 1560 cm-1 wave number in chitosan cross-linked tpp films were due to the presence of ionic interaction between the positive charged of amino group in chitosan and negatively charged of phosphate group by tpp. The pattern area from the XRD results showed that the covalent cross-linked had significantly changed on the chitosan`s degree of crystallinity. The water contact angle on the surface of covalent/ionic cross-linked chitosan film reached the highest θ at 82.72° which indicated more hydrophobic properties was formed. Covalent/ionic cross-linked chitosan also showed the higher mechanical strength with average tensile stress value at 71.25 MPa. All finding results demonstrated that cross-linked modification on the chitosan film had successfully reduced the film’s hydrophilicity and increased the mechanical properties of the film.

Precipitated calcium carbonate (PCC) is also known as synthetic calcium carbonate. In this paper, PCC was synthesized from carbide lime, which is the by-product from acetylene gas industry. The method used to produce PCC from carbide lime waste was ionic sucrose precipitation technique. The experiments were performed by varying the stirring rate. In this technique, carbide lime was first dissolved in ionic sucrose solution and then chilled at 10 °C for 24 hours before carbon dioxide gasses was introduced into the solution. The carbonation and precipitation process was took place and PCC was formed. The PCC was further filtered to obtain the solid PCC. The sample was then further characterised by using FESEM and XRD to determine the morphology and to identify the phase that exists in the synthesized compound respectively. The XRD and FESEM results clearly shown that the PCC obtained has mixed phases of calcite and vaterite, with mixtures of spherical and irregular shape morphologies formed. The irregular s...

The objective of the study is to synthesis as fine as possible the particle size of precipitated calcium carbonate (PCC). In previous study carbon dioxide gas was introduced into ionic solution to produce PCC. In this study ionic solution was introduced from a column into water with dissolved CO2 gas. Four experiments were carried out by flowing 1 L ionic solution (calcium sucrate) into 3 L beaker that contained water at average flow rate of 0.1 L/min. The CO2 gas was flowed into 0.5 L of water at the rate of 0.5 L/min and 1.5 L/min respectively. This was repeated using 0.6 L of water. The micrographs of Field Emission Scanning Electron Microscope (FESEM) show that fine particle size of PCC produced was 254.6 nm and cubic shapes were formed in all the products. Based on the pattern of X-ray Diffraction (XRD) results show that all PCC produced was calcite

Star polymers have unique characteristics due to their well-defined size and tailor ability which makes these polymers attractive candidates as carriers in drug delivery system applications. This work focuses on attaching a drug to the star polymer (polyamidoamine). The conjugation of polyamidoamine (PAMAM, generation 4) with methotrexate (MTX) (model drug) was studied in which monomethyl polyethylene glycol (MPEG) was used as a linker to reduce the toxicity of dendrimer. Conjugation starts with attaching the drug to the linker and followed by further conjugation with the polyamidoamine (PAMAM) dendrimer. The conjugation of PAMAM-PEG-MTX was confirmed through UV-Vis, FTIR, 1H NMR and DSC. The loading capacities and release profile of this conjugate were determined using 1H NMR and UV spectrometer.