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PRODUKSI GAS KARBON DIOKSIDA SELAMA PROSES BIOREMEDIASI LIMBAH HEAVY OIL DENGAN TEKNIK LANDFARMING Charlena, Charlena; Mas’ud, Zainal Alim; Anas, Iswandi; Setiadi, Yadi; Yani, Moh.
CHEMISTRY PROGRESS Vol 3, No 1 (2010)
Publisher : Sam Ratulangi University

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Abstract

Bioremediation is defined as biological degradation process of organic or inorganic wastes in a controlledcondition to control and reduce their amount in the environment. In this study, the soil which had been polutedby heavy petroleum oil fractions, i.e. heavy oil waste (HOW), was used as sample. The bioremediationtechnique used in this study is an ex-situ technique. This study was conducted to determine the amount ofproduced CO2 gas during the HOW degaradation process. Treatment of heavy oil waste with biostimulation andbioaugmentation. Production of CO2 gas were placed in impiger and analysis with titrimetry method. The highestCO2 production mean was obtained from the bioaugmentation treatment with compost adding, i.e. 244,5 mg/m3.Generally, graphs CO2 gas production followed a similar sinusoidal pattern. From these results it can beinfered that the degradation process of HOW happened during the treatments in aerobic condition.
PROFIL KELARUTAN LIMBAH MINYAK BUMI DALAM AIR AKIBAT PENGARUH SURFAKTAN NONIONIK DAN LAJU PENGADUKAN Charlena, Charlena
CHEMISTRY PROGRESS Vol 2, No 2 (2009)
Publisher : Sam Ratulangi University

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Abstract

Petroleum waste is classified as a dangerous waste that cause pollution and damage the environtment.The remediation of petroleum polluted soil could be done by microorganism capability. Additional ofnonionic surfactant and stirring rate would make soil dispersed well in water, facilitating good contactbetween microorganism and petroleum carbon as its feed. In this research, Tween 80 and Brij 35 wereused as surfactants. The observed parameters were concentrations and stirring rates. Surfactantconcentration was selected based on surface tension value and emulsion stability. The highest emulsionstability for Tween 80 observed was 0.24% at concentration 0.0175%, while for Brij 35 equal to 0.22% atconcentration 0.0150%. Stirring rates were applied 100, 120, and 140 rpm, successively based on liquidTotal Petroleum Hydrocarbon (TPH) value. Liquid TPH value at 100, 120, and 140 rpm for Tween 80 andBrij 35 were 0.25, 0.32, 0.40 and 0.36, 0.55, 0.74%, successively. Liquid TPH depicted amount of oil thatwas dispersed into the water. The other parameters such as solid TPH and Chemical Oxygen Demand(COD) obtained for 140 rpm were 15.56% and 41235 mg/L for Tween 80 while for Brij 35 equal to 16.55%and 41717 mg/L Keywords : petroleum waste, nonionic surfactant, stirring rate
Hydroxyapatite Coating on Alloys CoCrMo-TiN with Sol-Gel Method Charlena, Charlena; Giat Sukaryo, Sulistioso; Zuhfria, Moch. Irgham
Indonesian Journal of Fundamental and Applied Chemistry Vol 1, No 3 (2016): October 2016
Publisher : Indonesian Journal of Fundamental and Applied Chemistry

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Abstract

ABSTRACTHydroxyapatite 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 oC 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 sol-gel 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.Keywords: hydroxyapatite, CoCrMo-TiN, precipitation-sonification, sol-gel modified
Utilization of Electrolyte Solution in Nanotube Formation on Ti-6Al-4V Metal Alloy Charlena, Charlena; Kemala, Tetty; Wulanawati, Armi
Indonesian Journal of Fundamental and Applied Chemistry Vol 3, No 1 (2018): February 2018
Publisher : Indonesian Journal of Fundamental and Applied Chemistry

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Abstract

Formation of nanotube morphology on the surface of Ti-6Al-4V metal did not occur homogeneously, so when it was coated with hydroxyapatite, it did not merge well. One of the factor that affected the inhomogeneously formed nanotube was the utilization of electrolyte solution. The research has been done to observe the effect of electrolyte solution in the formation of nanotube morphology on the surface of Ti-6Al-4V metal alloy. Electrolyte solution that was used was ethylene glycol, HF, and NH4F with time variation of an hour, 2 hour, and 3 hour. Formation of nanotube morphology on the surface of Ti-6Al-4V metal alloy was done using anodization process. The result showed that in HF electrolyte solution which was anodized for an hour ɑ and β phase that composed Ti-6Al-4V metal alloy was formed, meanwhile when using electrolyte solution of ethylene glycol  + NH4F for 2 hours showed that there were pores that opened on Ti-6Al-4V metal alloy surface. Nanotube morphology on the surface of Ti-6Al-4V metal alloy was formed using electrolyte solution of ethylene glycol + NH4F which was anodized for 3 hours.
Studi Cemaran Timbal dari Gas Buangan Kendaraan Bermotor Terhadap Daun Pisang Disekitar Jalan Inderalaya-Palembang Aslihati, Aslihati; Lebani, Aldes; Charlena, Charlena
Jurnal Penelitian Sains No 13 (2003)
Publisher : Faculty of Mathtmatics and Natural Sciences

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Abstract

Penelitian dilakukan untuk mengetahui adanya kemungkinan pencemaran timbal dari kendaraan bermotor terhadap udara di sekitar jalan Inderalaya-Palembang melalui bioindikator daun pisang. Hasil yang diperoleh dibandingkan dengan tingkat cemaran timbal berdasarkan baku mutu makanan yang berlaku. Sampel daun pisang diambil dari sekitar jalan Inderalaya-Palembang dengan jarak tiap titik pengambilan ± 5 km, dengan titik sampling pertama di dimpang empat Musi II dan terakhir di persimpangan jalan Sarjana, Inderalaya OKI. Penentuan konsentrasi timbal dilakukan dengan metode spektrofotometri serapan atom non nyala. Hasil penelitian menunjukkan bahwa konsentrasi timbal dalam sampel daun pisang dari sekitar jalan Inderalaya-Palembang berkisar dari 0,006 ppm sampai 0,391 ppm, dengan konsentrasi terendah di daerah Sarjana, Inderalaya, OKI. Konsentrasi rata-rata keseluruhan lokasi adalah 0,19 ppm. Tingkat cemaran timbal dalam daun pisang masih dibawah ambang batas baku mutu makanan yang dikeluarkan oleh Dirjen POM tahun 1989 yakni 2 ppm.