ANALISIS DISTRIBUSI LOGAM BERAT DALAM TANAH, AIR, DAN TANAMAN SINGKONG SEKITAR PLTU PACITAN DENGAN METODE k0-AAN

ERRY NANDYA NOVIARIZ, Dr. Roto, M. Eng.; Prof. Dr. Ir. Agus Taftazani

2015 | Skripsi | S1 KIMIA

Logam berat pada sampel tanah, air, dan tanaman singkong sekitar PLTU Pacitan dianalisis dengan metode k0-AAN sehingga pola distribusi logam berat dapat ditentukan. Metode k0-AAN divalidasi terlebih dahulu dengan penentuan z-score. Hasil analisis digunakan untuk menentukan Faktor Bioakumulasi (BCF). Sampel tanah ditumbuk dan diayak. Sampel daun dan tanaman singkong dikeringkan dengan freeze drier dan N2 cair, ditumbuk, dan diayak. Sampel air dipreparasi dengan cara diuapkan hingga volumenya menjadi 1/40 volume awalnya. Au-Zr foil digunakan sebagai monitor fluks reaktor. Sampel padat dan sampel cair diiradiasi bersama dengan monitor fluks, SRM, standar sekunder dan blanko. Interpretasi sampel pada penelitian ini dilakukan dengan bantuan software Genie 2000, Hypermet 5.12, dan k0-IAEA. Metode k0-AAN dianggap baik dimana nilai |z-score|>2. Tujuh logam berat berhasil terdeteksi di dalam sampel, yaitu Sc, Cr, Fe, As, Co, Cu, dan Zn . Fe diketahui merupakan logam mayor dalam sampel tanah, air, daun singkong, dan umbi singkong dengan konsentrasi berturut-turut 121300 ppm; 12,515 ppm; 567,85 ppm; dan 264,75 ppm. Sementara, As diketahui merupakan logam minor dalam sampel tanah, daun singkong, dan umbi singkong dengan konsentrasi berturut-turut 12,595 ppm; 0,241 ppm; dan 0,207 ppm. Logam As dan Sc tidak terdeteksi pada sampel air. Urutan konsentrasi logam berat dalam sampel adalah tanah>daun>umbi>air. Berdasarkan nilai BCF, terdapat indikasi akumulasi Zn di dalam daun singkong.

Heavy metals in soils, water, and cassava plants around Pacitan Coal-fired Power Plant were analyzed using k0-NAA method so that their distribution pattern could be determined. The k0-NAA method was validated first by determining z-score. The results of analysis were used to determine Biocentration Factor (BCF). The soil sample was ground and sieved. The cassava leaves and cassava roots were freeze dried with liquid N2, ground, and sieved. The water sample preparation was performed by evaporating it until the volume was 1/40 from the original. Au-Zr foil was used as flux monitor. The samples were irradiated together with flux monitors, secondary standards, SRMs, and blanks. Samples interpretation was performed with support of Genie 2000, Hypermet 5.12, and k0-IAEA software. The k0-NAA method was considered valid based on the analysis results of SRM where |z-score|>2. Seven heavy metals were successfully determined in the samples, that are Sc, Cr, Fe, As, Co, Cu, and Zn. Fe was found to be the major metal in the soils, water, cassava leaves and cassava roots with concentration of 121300 ppm, 12.515 ppm, 567.85 ppm, and 264.75 ppm respectively. Meanwhile, As was found to be the minor metal in the soils, cassava leaves, and cassava roots with concentration of 12.595 ppm, 0.241 ppm, and 0.207 ppm respectively. As and Sc were not detected in the water samples. The order of heavy metals concentration in the samples was as follows soil>leaf>root>water. Based on BCF value, there was indication of Zn accumulation in cassava leaves.

Kata Kunci : logam berat, PLTU Pacitan, k0-AAN, monitor fluks, k0-IAEA.