Removal of Chromium from Industrial Wastewater by Adsorption Using Coffee Husk

Abstract

Fresh water is vital to human life and economic well-being, and societies extract vast quantities of water from rivers, lakes, wetlands, and underground aquifers but most of these freshwater sources are polluted by different chemicals discharged from industries. Our need for fresh water has long caused us to overlook equally vital benefits of water that remains in streams to sustain healthy freshwater habitats.Heavy metals are discharged from different industries into freshwaters and are easily absorbed by fish and other aquatic organisms. Small concentrations can be toxic because heavy metals undergo bio concentration. Chromium is an essential element that is required in small amounts for carbohydrate metabolism, but becomes toxic at higher concentrations. The most bioavailable and therefore most toxic form of chromium is the hexavalent Cr (VI) ion. It is well recognized as an element of environmental and public health concern. The objective of this study was to examine the potential of coffee husk in removing chromium from polluted water.In this study, the adsorption potential of activated carbon for the removal of Cr (VI) ions from industrial wastewater has been investigated. The adsorption of hexavalent chromium from aqueous solution by coffee husk activated carbon prepared by chemical method and its application to real wastewater was studied. The extent of adsorption was studied as a function of pH, contact time, adsorbent dose, and initial adsorbed concentration. Optimum results were found to be 60 min, 80 mg/l, 2 g/l, 3 g/l and 200 rpm for time contact, initial concentration, pH, adsorbent dose and stirring speed respectively at the optimal condition the adsorption of hexavalent chromium was found to be 98.19%.

Preparation and characterization of higher degree‐deacetylated chitosan‐coated magnetic adsorbent for the removal of chromium(VI) from its aqueous mixture

“…Before analyzing the initial Cr(VI) concentration of the tannery wastewater samples, it undergone the acid digestion (using nitric acid) process and then filtered off using Wattman filter paper (No. 41) . The pH values of the samples were adjusted from its initial values into 5.5.…”

Adsorption of Chromium(VI) onto Freshwater Snail Shell-Derived Biosorbent from Aqueous Solutions: Equilibrium, Kinetics, and Thermodynamics

“…Chromium is a highly toxic agent to humans and other living organisms, which is discharged into receiving sources from many industrial activities, including leather tanning, electroplating, metal processing, dyeing, chromate preparation, and leathers [1]. In aqueous solutions, chromium exists in both trivalent (Cr(III)) and hexavalent (Cr(VI)) forms [2][3][4][5]. Compared with Cr(III), Cr(VI) is more mobile, hard to treat, and about 10-100 times more toxic [1,6].…”

“…Biosorbents are adsorbents derived from various kinds of biomass, mainly industrial and agricultural by-products, such as clay, corncob, and fly ash [2,14,15], which are used for the removal of various contaminants from the water environment. Among them, a large number of low-cost biosorbents developed from different by-products, such as tamarind nut carbon [12], green coconut shell [3], sugarcane bagasse [4], coffee husk [5], rice husk [16], waste fruit cortexes [17], and mango kernel [18], had been used for aqueous Cr(VI) adsorption. Especially, the materials containing biogenic calcium carbonate (CaCO 3 ) have been attracting much attention from scholars.…”

Removal of Hexavalent Chromium from Aqueous Solution by Adsorption on Palm Oil Fuel Ash (POFA)

“…Agricultural wastes which are abundant in source are mainly consisting of cellulosic structure, which makes them an effective adsorbent for heavy metal ions (Guiza, 2017). Several recent studies involving agricultural wastes as adsorbent for Cr(VI) removal included usage of bamboo (Dula et al, 2014), rice straw (Kumar et al, 2017), coffee husk (Berihun, 2017), tea wastes, coconut shell and orange peel (Amir et al, 2017). In this study, palm oil wastes in the form of ash were used for Cr(VI) removal.…”