The effect of CO2 flow rate and carbonation temperature were studied in the synthesis of PCC from limestone using carbonation method. The synthesis was started by dissolving CaO that was obtained from calcination of limestone into HNO3 6M. The solution was then added with ammonia solution and then streamed with CO2 until pH 8 with flow rates of 0.5; 1.0; 1.5; and 2.0 L/min. The optimum flow rate obtained from this stage was then applied in the carbonation process with temperatures of 50, 80, 100, 150, 200, and 250 °C. The results showed that low flow rate give reasonably high yield but the yields obtained in every flow rate used in this work has insignificant difference based on F-test. The optimum flow rate used for the synthesis of PCC in the next stage was 0.5 L/min with a yield of 62.95%. Different carbonation temperature influences the polymorphs and crystallinity of the synthesized PCC. The synthesized PCC was analyzed by FT-IT, powder-XRD, SEM-EDX, and PSA. FT-IR analysis showed stretching vibrations of C–O at 1419, 1479, and 1384 cm-1 which correspond to calcite, vaterite, and aragonite respectively. Powder-XRD and SEM-EDX confirms that at the carbonation temperature of 50 °C, calcite and vaterite were formed, while at the carbonation temperature of 80 °C, mixture of calcite-vaterite-aragonite were obtained. Higher carbonation temperature changes the vaterite and aragonite polymorphs into calcite, and the best crystallinity was obtained at 250 °C. PSA analysis showed that the particle diameter of the synthesized PCC was about 3.58 to 38.14 µm.

The limestones was abundant in Tuban, East Java and have high calcium mineral content. Nevertheless, in the economic value, limestone have low price. Aim the research is prepare Precipitated Calcium Carbonate (PCC) by caustic soda method. In this method, calcium was dissolved in HNO 3 with different concentration (2, 4,6, 8 M). The Filtrate obtained then was added by Na 2 CO 3 1 M to get PCC. As the results, The white PCC obtained with the highest rendement is 64,7% when added HNO 3 6M. Analysis of functional group by FTIR show that there were strong absorption in the 844,76; 912,27 dan 1411,40 cm -1 that indicated carbonate group. Analysis of Cristallinity by XRD show that there were the peak characteristic of 2 on 29,50˚; 36,07˚ dan 39,50˚that representative calcite structure. SEM -EDX Analysis show that PCC have a mixing structure of calcite and vaterite.

Salah satu material yang bersifat biokompatibel serta sering digunakan sebagai bahan dasar implan tulang dan gigi adalah trikalsium fosfat. Material ini dapat dihasilkan dari precipitated calcium carbonate (PCC) batu kapur karena memiliki kandungan kalsium yang sangat tinggi. Metode yang digunakan untuk mensintesis trikalsium fosfat yaitu melalui pengendapan prekursor CaO dan H3PO4 dalam media etanol. Hasil sintesis dikarakterisasi menggunakan instrumen FT-IR, AAS, spektroskopi UV-Vis, dan XRD. Dari hasil analisis spektroskopi UV-Vis, rasio Ca/P dari hasil sintesis diperoleh sebesar 1,64. Uji FT-IR menunjukkan adanya gugus Ca-O pada bilangan gelombang sekitar 1400 cm-1 dan gugus PO43- pada bilangan gelombang 561 cm-1 dan 1041 cm-1. Uji XRD menunjukkan 3 puncak tertinggi dari β-TCP (trikalsium fosfat) yang sesuai dengan JCPDS no. 09-0169.One of the biocompatible materials that are often used as a basic materials for bone and dental implants is tricalcium phosphate. This material can be produced from precipitated calcium carbonate (PCC) limestone because it has a very high calcium content. The method used to synthesize tricalcium phosphate was deposition of CaO and H3PO4 precursors in ethanol media. The results of the synthesis was characterized using FT-IR instruments, AAS, UV-Vis spectroscopy, and XRD. Based on the results of the UV-Vis spectroscopic analysis, the Ca/P ratio of the synthesis results obtained was 1.87. FT-IR test showed the presence of a Ca-O group at wave number 1400 cm-1 and PO43- group at wave numbers 561 cm-1 and 1041 cm-1. XRD test showed highest peaks of β-TCP (tricalcium phosphate) according to JCPDS no. 09-0169.