MAGNETIK PROPERTIES OF NICKEL HYPERACCUMULATING PLANTS FROM ULTRAMAFIC REGION

• Main Author: Mujahid Hamdan, Abd
• Format: Dissertations
• Language: Indonesia
• Subjects: Fisika terapan
• Online Access: https://digilib.itb.ac.id/gdl/view/37228
• Institution: Institut Teknologi Bandung

Nickel (Ni) hyperaccumulating plants are plants that can accumulate Ni higher than 1.000 ?g/g in their dry biomass. These plants were considered potentially for remediation and mining. Remediation with hyperaccumulating plants termed as phytoremediation, meanwhile mining with hyperaccumulating plants termed as phytomining. Ni phytomining was considered as a green and low cost method for applying on ultramafic regions. Indonesia has large ultramafic regions, but native Ni hyperaccumulators Indonesia from ultramafic areas are still very limited. Even though, species variety is a one of factor of phytomining successful. Thus, identifications of Ni hyperaccumulators are needed to support applying of Ni phytomining. Magnetic methods were considered as rapid and efficient method to analysing minerals and metals in natural matters. Meanwhile, beside on their ability to absorb Ni in extreme concentrations, Ni hyperaccumulators also have ability to absorb the others metals simultaneously. Even, these abilities are correlated to Ni accumulating. Among metals absorbed by Ni hyperaccumulators, there are elements that have magnetic properties, including iron and cobalt. Therefore, magnetic methods suspected can be used to identify new Ni hyperaccumulators, especially species from ultramafic regions. This study aimed to investigate the ability of magnetic method to identify Ni hyperaccumulating plants. Characterized species are Planchonella oxyhedra and Rinorea bengalensis. As comparison, magnetic characterizations also conducted to non-native Ni hyperaccumulators Indonesia that consisted of: Alyssum murale and Alyssum corsicum. For Ni concentrations analyses in the samples by atomic absorption spectroscopy (AAS) analysis. Those measurements were supported by x-ray diffraction (XRD), x-ray fluorescence (XRF) and scanning electron microscopy energy dispersion spectroscopy (SEM-EDS) analysis. Ni hyperaccumulators have positive magnetic susceptibility, ?, meanwhile, nonhyperaccumulators have negative ? values. ? values of P. oxyhedra are 12 to 21 (×10–9) m3/kg, with an average value of 17.83? 3.07 (×10–9) m3/kg, meanwhile ? values of R. bengalensis are 23 to 33 (× 10–9) m3/kg with average value of 30.16? 5.84 (× 10–9) m3/kg. These results indicate that Ni hyperaccumulators and nonhyperaccumulators can be identified by ? values. By the magnetic method, two species were found i.e. Caesarea halmaherensis and Piper sp., respectively Ni concentration of the samples are 2,546? 230.4 ?g/g and 2745.4? 990 ?g/g. These finding indicate that magnetic method can be used as a supplementary method to identify new Ni hyperaccumulators species.