Heavy metal ions adsorption from pulp and paper industry wastewater using zeolite/activated carbon-ceramic composite adsorbent

Abstract

Leachate wastewater from pulp and paper industry is known for containing various types of heavy metals such as Cd (Cadmium), Ba (Barium) and Cu (Cuprum). The existence of heavy metals that accumulates and eventually exceeds certain threshold concentrations will cause environmental pollution, therefore it is necessary to conduct wastewater treatment to eliminate or at least reduce the heavy metal content in industrial wastewater. One of the most commonly used wastewater treatment method is using adsorbent, this study uses adsorbent made from the mixture of clay, zeolite and activated carbon formed into ceramic balls with ± 0.5 cm diameter. The ratios of the mixture of clay, zeolite and activated carbon are 6:3:1; 6:2,5:1,5; 6:2:2; 6:1,5:2,5 and 6:1:3 with variations of contact time 30, 60, 90, 120 and 150 minutes. The most favorable concentration reduction of heavy metals occurred at the longest contact time of 150 minutes at 6:3:1 adsorbent ratio, Cd concentration decreases from 0.65 mg/L to 0.03 mg /L, Ba concentration decreases from 0.86 mg/L to 0.04 mg/L and Cu concentration is from 0.6 mg/L to 0.02 mg/L. These prove that the ceramic zeolite/carbon-ceramic composite adsorbent can be an alternative to treat wastewater containing heavy metals derived from the pulp and paper industry.