Coconut fruit has many benefits. Coconut meat can be used as ingredients, usually used as a coconut milk. Santan is a coconut juice extract. Coconut milk is taken from the juice of coconut meat that has been shredded before. Dregs from grated coconut meat that has been squeezed to take the coconut milk and usually just thrown away or used to mix animal feed.
But after innovations by Raden Wahid Hanafi and Nenny Widiani students of FMIPA UNY Chemistry Study Program, it turns out that coconut pulp can be used as Cr (III) (Chromium) Metal Ion Adsorbent ..
Wahid said, metal ion Cr (III) is a metal harmful to health. Cr (III) metal ions are mostly produced from waste products from the electroplating and leather tanning industries. Cr (III) metal ions are carcinogenic. Cr (III) metal ions cannot be digested by the body and if it enters the human body Cr (III) metal ions will accumulate in the body and can cause dangerous diseases.
Many efforts to control heavy metal waste Cr (III) have been carried out. Various adsorbents have been used to reduce the Cr (III) content in waste, but the results have not been satisfactory. So the adsorbent is still needed from new materials or materials such as coconut pulp.
The stage of making coconut pulp powder adsorbent is divided into 2 stages, namely making coconut pulp charcoal using the roasting method and sifting coconut pulp charcoal using a 50 mesh sieve.
Coconut pulp is used as an adsorbent because it contains cellulola, manan, and galactomannan. Cellulose and galactomannan have active sites. The active site is able to bind heavy metal ions. In addition, coconut pulp has pores that can trap heavy metal ions.
After making charcoal using coconut pulp, the next step is to absorb heavy metals Cr (III) with the charcoal. Cr (III) is obtained from a solution of CrCl3. One gram of coconut pulp charcoal is put in 25 ml of CrCl3 solution with concentrations of 50, 100, 150, 200, and 250 ppm. The adsorption process is carried out by stirring for 1 hour then left for 1 day and 1 night.
Based on this study, coconut pulp made into charcoal can be used effectively to adsorb Cr (III) heavy metal ions at a concentration of 100 ppm with absorbed Cr (III) concentrations of 94,046 ppm and absorption capacity of 2,351 mg / g. (witono)