Pemanfaatan Kulit Jengkol (Pithecellobium jiringa Prain) Sebagai Adsorben Dalam Penyerapan Logam Pb (II) Pada Limbah Cair Industri Pelapisan Logam

Abstract

The aim of this research is to study the effect of activation temperature, activation time, drying temperature, drying time and ratio of jengkol peel with nitric acid to iodine number of adsorbent jengkol peel and to study the optimum adsorbent mass to reduce metallic lead (Pb) concentration in electroplating wastewater. Materials used for this research were electroplating wastewater, jengkol peel, nitric acid, and distilled water. Jengkol peel was cleaned and mashed to a size of 100 mesh of sieve tray and then activated with a solution of nitric acid (HNO3) 4 N with jengkol peel : nitric acid ratio 20: 0.5; 20: 1 and 20: 2 mg / mL while heated at temperature 70, 80 and 90 ° C for activation time 60, 90 and 120 minutes. Adsorbent dried in oven at temperature 100, 110 and 120 °C for drying time 60, 90 and 120 minutes. Adsorbent with optimum iodine number then used in batch adsorption of Pb (II) that carried out by stirring activated adsorbent in the wastewater at pH 5 using variations of mass 0.5; 1 and 1.5 g per 50 mL of liquid waste on a hot plate by stirring using a magnetic stirrer at 30 rpm for 30 minutes. The results showed that the optimum ratio of jengkol peel : nitric acid is 20: 1 mg/mL at activation temperature 90°C, activation time 120 minutes, drying temperature 110 ° C and the drying time 120 minutes with iodine number 634.50 mg/g. The optimum mass of adsorbent is 0.5 grams with Pb (II) adsorption capacity of 0.92 mg/g. Iodine number of jengkol peel adsorbent was found to be less than 750 mg/g, an activated carbon iodine number standard by SNI.