Abstract

Removal of Chromium (VI) from Printing Waste using Activated Natural Zeolite

Author(s): Adi Ilcham

Increasing industrial activity is producing increasing amounts of waste. Waste from the printing industry can harm the environment as it contains chromium, a toxic metal pollutant. There are two oxidative forms of chromium in the aquatic environment: Cr (VI), which is highly toxic and Cr (III), which an essential element for humans and animals. This study investigates the removal of Cr (VI) from liquid waste using activated natural zeolites as an adsorbent. The effects of activator concentration, contact time and stirring speed on Cr (VI) removal were studied. We used an artificial liquid waste made from a mixture of K₂Cr₂O₇, water and used newspapers. The artificial liquid waste was placed in beakers with zeolite adsorbent and stirred at various speeds for various lengths of time. Then, the Cr (VI) content was analyzed using a UV-Vis spectrophotometer. The optimal conditions were determined to comprise natural zeolite crushed to 40 mesh size and activated by 0.75 N NaOH and stirring for 60 min at 120 rpm. This procedure removed 87.60% of the Cr (VI) from the liquid waste.