Chemically Modified Crop Residues as a Low-Cost Technique for the Removal of Heavy Metal Ions from Wastewater

Abstract

Batch adsorption experiments were carried out to evaluate the effect of type of crop residues and chemical pretreatment solutions on the removal efficiency of heavy metal ions at different concentrations of synthetic wastewater solutions. Rice straw, cotton stalks, and maize stalks were pretreated with different solutions (i.e., sulfuric acid, oxalic acid, sodium hydroxide, and distilled water as the control treatment) in order to increase their metal-binding capacity. Results indicated that cotton stalks were the best biosorbent material according to their efficiency in removal of heavy metal ions. Sodium hydroxide was the best chemical pretreatment method for stimulating the biosorption capacity of crop residues. Ions of Pb 2+ had the highest biosorption ratio among all competitive ions, whereas Mn 2+ ions had the lowest. The removal efficiency decreased as the concentration of heavy metal ions increased in aqueous solutions. Sorption equilibrium isotherms could be described by the Langmuir model in most cases, whereas an isotherm of S shape was observed in other cases, which did not follow the Langmuir isotherm model. In conclusion, cotton stalks pretreated with sodium hydroxide could be used as an efficient technique for wastewater remediation prior to irrigation due to its low-cost, little processing, and high biosorption capacity.

Capability of some agricultural wastes for removing some heavy metals from polluted water stocked in combination with Nile tilapia, Oreochromis niloticus (L.)

“…Kelly-Vargas et al (2012) reported that lemon peel and orange peel demonstrated adsorption capacities for Cu and Pb were 48 and 15% higher than banana peel, respectively, and the Cd uptake by banana peel was higher than that of lemon peel and orange peel 82 and 57%, respectively. On the other hand, Mosa et al (2011) reported that the removal efficiency of metals Means followed by the same letter are not significantly different decreased in the order of cotton stalks, maize stalks, and rice straw. They attributed highest removal by cotton stalks to its highest concentration of cellulose, hemicellulose, and lignin as compared to other crop-residues.…”

“…Adsorption is generally known to be one of the most effective techniques for HM removal from wastewater (Benhima et al 2008;Zafar et al 2007;Gupta and Babu 2009;Mosa et al 2011;Chiban et al 2012;WitekKrowiak and Reddy 2013). Considerable attention has been paid to the development of effective and low-cost adsorbents.…”

Sorption of lead by chemically modified rice bran

“…Some earlier studies reported that inexpensive residues have the capability to adsorb heavy metals from polluted water and metal solutions, e.g., sunflower stalks (Sun and Shi 1998), waste tea (Mahvi et al 2005), wheat bran (Bulut and Baysal 2006), almond shells (Dakiky et al 2002) and distillery sludge from the sugar cane industry (Nadeem et al 2008). Mosa et al (2011) suggested that pretreated agricultural biosorbents enhanced the sorption capacity. The main residues of agricultural products are lignin and cellulose, but various supplementary compounds are also found (Sud et al 2008).…”

Chelating–Ultrafiltration Treatment of Some Heavy Metal Ions in Aqueous Solutions by Crosslinking Carboxymethyl Modified Cornstarch

“…Biosorption of heavy metals from aqueous solutions is a relatively new process that has been proved fairly promising in removal of these contaminative elements from industrial effluents (Aderhold et al 1996;Bailey et al 1999;Basso et al 2002;Ahalya et al 2003;Matis et al 2003;Ahmed et al 2010). Deriving from low-cost agricultural product, this way is now considered as an effective, efficient, and economic method for water decontamination, as well as elementary separation for analytical purpose (Basso et al 2002;Ahalya et al 2003;Carletti et al 2008;Ahmed et al 2010).…”

“…Deriving from low-cost agricultural product, this way is now considered as an effective, efficient, and economic method for water decontamination, as well as elementary separation for analytical purpose (Basso et al 2002;Ahalya et al 2003;Carletti et al 2008;Ahmed et al 2010).…”