PENGAMBILAN TANIN DARI KULIT KAYU BAKAU DAN PEMANFAATANNYA SEBAGAI ADSORBEN LOGAM BERAT CUPRUM (Cu) DAN TIMBAL (Pb)

Abstract

<p><strong><em>Abstract: </em></strong><em>Mangrove bark contains tannins which can be modified into mangrove tannins based adsorbent (MTBA) for heavy metals. This research aimed to study the performance of mangrove tannins for removing Copper (Cu) and Lead (Pb). This experiment had three steps : extraction of mangrove barks, modification tannins into MTBA, and adsorption of Cu and Pb solutions with MTBA. Alcohol 70% was used for extraction of mangrove barks. The research was coducted at stirred glass flask equipped with heater. The research run at extraction time variation (1, 1.5, 2, 2.5, and 3 hours) and extraction temperatur variation </em><em>(50, 55, 60, 65, and 70 ºC). Mangrove tannins were dissolved into NaOH solution and formaldehyde 37% then heated forming powder MTBA. The adsorption equlibrium of Cu and Pb solution by MTBA was studied. The result showed that increasing extraction time and extraction temperature will increase the yields.The optimum condition for tannin extraction was extraction temperature 70 <sup>o</sup>C and extraction time 3 hours with tannin yield 21.105%. The result also showed that MTBA can adsorp 79.94% of Pb and 43.75 of Cu from solutions.The Langmuir’s method was more suitable for predicting the Cu and Pb adsorption with Langmuir’s equilibrium constant k<sub>Cu</sub> = 0.0011 and k<sub>Pb</sub> = 0.0289.</em></p><p><em> </em><strong><em>Keywords:</em></strong><em> mangrove bark, tannin, extraction, adsorption, heavy metal.</em></p>