Removal of trivalent chromium from tannery waste waters using bone charcoal

Abstract

The ability of bone charcoal to remove Cr(III) from aqueous solutions by adsorption has been investigated. The adsorbent used was first characterised and then the adsorption was studied as a function of time and amount of charcoal. Tests were carried out with synthetic solutions whose Cr concentrations (500 mg L(-1)) were similar to those found in some effluents of Moroccan tannery industries. Cr removal efficiencies higher than 90% were obtained at pH 3.5 using 3 g of bone charcoal and a stirring time of about 30 min. Results of Cr removal by all sieved fractions of bone charcoal had shown the same interesting capabilities for Cr(III) retention. The cross interference with other elements was also investigated. Pre-treatment of bone charcoal by nitric acid led to an increase in its specific surface area but induced a drastic reduction in its Cr elimination abilities. Adsorption tests were also carried out using calcinated bone charcoal. The results obtained showed a similar percentage of Cr retention to those found with untreated bone charcoal. On the other hand, a double treatment of bone charcoal with HCl and NaOH provided an enhancement of Cr(III) retention. The role played by the mineral fraction of the solid phase of bone was thus evidenced.

Removal of Toxic Heavy Metals from Contaminated Aqueous Solutions Using Seaweeds: A Review

“…Polymers Fe and Cr [74] Sawdust and tree barks Hg, Pb, and Zn [75] Electronic waste along with galvanic wastes Cu, Ni, Mn, Pb, Sn [76] charcoal: Cr(III) [77] Clay Cr(III) [78] Fungi Cr, Fe [79] Dead biomass Cr [80] Peat moss Cr, Fe [81] Peanut shells, Rice husk, Straw, and walnut cover Cr, Cu, Ni [82] Cocoa shell Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn [83] Coconut husk Cr, As [82] Caol and fly ashes Cr, Cu, Ni [84] Banana pith and peels Ni, Pb [85] Cassava fiber Pb, Co [86] Chicken feathers Al, As [87] Sheep manure wastes Ca, Cd…”

Bone Char Adsorption of COD and Colour from Tannery Wastewater: Breakthrough Curve Analysis and Fixed Bed Dynamic Modelling

“…Different adsorbents have been developed from waste materials, such as rice husks [19], fly ash [25], tea leaves [26], shrimp shells [27], teff husks [28], moringa seeds [29], bone char [30], neem leaves, and tamarind tree bark [31], for removal of contaminants such as chromium, colour, turbidity, and biochemical oxygen demand from tannery wastewater. Among these adsorbents, bone char manufactured from animal bones, a common waste product from slaughterhouses, which has proven to be a very promising adsorbent in the removal of fluorides [32], heavy metals [33,34], and methylene blue [35] from various kinds of aqueous media will be used in this study for the adsorption of COD and colour from tannery wastewater.…”

Current Status of Trace Metal Pollution in Soils Affected by Industrial Activities

“…This activity adversely affects the quality of air, soil, and ground water, such that it becomes a subject of serious concern worldwide [6–8]. In recent years, many governments and policy makers have continued to strive for a more comprehensive understanding of environmental health hazards due to intensive industrial activities in order to inform future policy and abatement legislation [9].…”