- Turkish Journal of Engineering and Environmental Sciences
- Vol: 24 Issue: 5
- Removal of Chromium from Leather Industry Waste Water by Activated Clinoptilolite
Removal of Chromium from Leather Industry Waste Water by Activated Clinoptilolite
Authors : Remzi TOPRAK
Pages : 343-351
View : 6 | Download : 2
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :Possible use of acid activated Balğkesir-Bigadiç clinoptilolite for the removal of chromium from leather industry wastewaters was investigated. HNO3, H2SO4 and HCl were used for the activation of clinoptilolite and the effects of pH, acid concentration, particle size, solid/liquid ratio, time and temperature on activation were determined by chromium adsorption tests. Experimental results show that chromium can be adsorbed in the form of Cr2O72- ions at pH=1.35 and the adsorption capacity of the clinoptilolite depending on the acid used for activation decreases in the order HNO3>H2SO4>HCl. A series of tests considering Cr concentration, clinoptilolite/Cr solution ratio and time were carried out using samples activated with 2M HNO3 and 3M H2SO4. It was observed that the chromium adsorption capacities of the clinoptilolites activated with HNO3 and H2SO4 (Cr concentration=100 ppm, clinoptilolite/Cr solution ratio=1/2 mg/ml) for durations of 60 and 120 minutes were 0.061 mg/g and 0.064 mg/g respectively. Finally, adsorption tests were done with wastewater obtained the from U¤ur-Gül Leather Company containing 3120 ppm Cr under pre-determined optimum conditions and adsorption capacities for HNO3 and H2SO4 activated clinoptilolite samples were determined as 0.624 mg/g and 0.201 mg/g respectively. Upon dilution of the chromium content of the wastewater to 100 ppm, these values decreased to 0.045 mg/g and 0.019 mg/g.Keywords : Adsorption, Acid activation, Chromium, Clinoptilolite, Zeolite.