The more commonly used method for making synthetic zeolite from kaolin is hydrothermal method. This research tested a sol-gel method in processing synthetic zeolit  using kaolin as the basic ingrediant. The synthetic  zeolite  derived from the sol-gel method was then characterized using X-ray Difractometer and Scanning Electron Microscope, which found resulting products zeolite-A, zeolite Y and sodalite. The adsorption ability of the synthetic zeolites was tested using Cu(II) and methylene blue.  Functionalization of the synthetic zeolites by 3-(trimetoksisilil)-1-propantiol was  done to increase adsorption capacity. Zeolite A modified by 3-(trimetoksisilil)-1-propantiol  had the greater capacity to adsorb methylene blue at 30.11 mg/g. The adsorption isotherms of all the synthetic zeolites approached the Langmuir form. The adsorption energy off all synthetic zeolites approached the chemical adsorption.DOI: http://dx.doi.org/10.15408/jkv.v0i0.5144

Hydroxyapatite is synthesized by precipitation-sonification using calcium from field snail shell and powder phosphorus from (NH4)2HPO4. The calcium value was measured by atomic absorption spectrophotometer was 82.82%. The temperatures were varied on 600, 800, and 1000 o C to determine the best temperature of the coating. The best temperature was used to superimpose the HAp on the CoCrMo-TiN metal alloy using the modified solgel method. The layer on the metal alloy was identified with x-ray diffraction (XRD) and corrosion test. The XRD result showed that most of the CoCrMo-TiN metal alloy surface was coated by HAp. Beside HAp, there were several other phases such as calcium phosphate, carbonate apatite type A and type B. The best result of the corrosion test was showed in CoCrMo-TiN metal alloy coated with HAp with the smallest corrosion rate 0.0082 mpy.

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Hydroxyapatite (HAp) is a major component of bones and teeth. HAp is widely used to repair, fill, extend, and reconstruct damaged bone tissue. HAp is used for bone and dental implants, so it is necessary to synthesize HAp. HAp synthesis can utilize green mussel shell waste as a calcium precursor. This research synthesized HAp from a green mussel shell using the sol-gel method. The controlled synthesis parameter was pH, and the variable being compared was the heating temperature at 900 and 1100 °C. The HAp products were characterized by an X-ray diffractometer (XRD), Fourier-transform infrared spectrophotometer, and scanning electron microscope. The results showed that HAp was formed at alkaline pH, namely at pH 11. The XRD pattern showed that Hap was formed along with type A apatite carbonate, octacalcium phosphate, α- and β-tricalcium phosphate. The crystallinity was increased by raising the temperature and prolonging the heating time. The quality of HAp will improve with increasing crystallinity, and increasing the temperature will also raise the amount of HAp formed.

The heavy oil waste (HOW) containing polyaromatic hydrocarbon (PAHs) is a persistent organic pollutants (POPs) that difficult to degrade. The new PAH degrading consortium was investigated from HOW contaminated soil in North Sumatera of  Indonesia. The isolation, selection and identification of polyaromatic hydrocarbon degrading bacteria from soil contaminated by HOW was conducted to solve a bioremediation process. The isolation microbes from soil contaminated by HOW was performed using a minimum ONR7a media and followed on marine agar media for purification purposes. From the performed isolation results, 11 isolates were able to degrade PAHs compounds, such as phenanthrene, dibenzothiophene, or fluorene compounds. They grew at pH range of 4.8-8.2 and performed on emulsification activity in paraffin from 0.150-0.662. Three of them showed the best performance on HOW biodegradation capability and then successfully selected and identified as Salipiger sp., Bacillus altitudinis, and Ochrobactrum anthropi. using 16S rDNA. The HOW biodegradation as TPH-degradation were 38.66%, 59.60%, and 47.16%, respectively. Those isolated bacteria could potentially be as bioremediation agents to develop on bioremediation process for soils contaminated by HOW.