DESORPTION AND RECOVERY OF CHROMIUM HEXAVALENT FROM BIOSORBENT MICROALGAE

• Main Author: Akbar Devianto, Luhur
• Format: Theses
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/32085
• Institution: Institut Teknologi Bandung

Chromium is common pollutant introduced into natural waters due to the discharge of a variety industial wastewater which form hexavalent and trivalent. Chromium hexavalent is mobile in the environment and highly toxic and carcinogenic. There are many technology in chromium removal. One of them is biosorption. In this research, biosorption chromium hexavalent in batch system was done for 180 minutes at 180 rpm at pH 1 using chromium artificial waste with initial concentration 100 ppm. Chromium effluent concentration was determined by colorimetry method using 1,5-diphenylcarbazide as complexing agent and measured using spectrofotometer. The results show that the biosorption mechanism folows isotherm Langmuir with qm and Kads as much as 20.284 mg Cr(VI)/gram sorbent and 0.002825, with reaction kinetics follow pseudo-second-order. In the next stage of this research, desorption were carried out using several type of eluent such as acid and alkaline in various concentration. The eluent were HNO3 0.1N; 1N; H2SO4 0.1N; 1N; 4N; KOH 0.1N; 1N; NaOH 0.1N; 1N. The results show that the largest percent desorption was performed by using H2SO4 4N as much as 78.84% with desorption kinetics follow second order. In this research, We also determining biosorbent performance after several desorption phase. Results of repetition of biosorption after desorption using H2SO4 4 N showed the best performance with percents removal as much as 80.1%, 93.86%, and 90.32% respectively. At this research biosorption could be peformed up to three times. While, biosorption after desorption using KOH and NaOH had low performance at second biosorption which indicated by the decreasing initial percent removal 80.1% to become 19.95% and 23.48%. In order to recover chromium metal, electrolysises were conducted. The best result was performed by carbon as anode at 12 volts with chromium removal at electrolyte as parameter which could reducing chromium as much as 88.28%.