197
and peanut hulls exhibited good results toward cadmium adsorption. Some other
adsorption studies conducted using activated carbon prepared coir pith, bagasse
pith, and dates and peanut shells. Their cadmium adsorption capacity was found to
be up to 98%. One study showed that tea-based adsorbent reduced almost 70% of
the hexavalent chromium into Cr(III). In short, agricultural waste can be used as
low-cost and most beneficial adsorbent for removal of heavy metals from aqueous media.
Keywords Environmental issues · Industrial effluents · Heavy metals · Adsorbent
· Nanocomposites · Agricultural waste · Chitosanyremediation
8.1 Introduction
Environmental contamination related to the substantial release of heavy metal in
wastewater coming from quick industrial development and urbanization is a worldwide concern. Therefore, different conventional treatment strategies have been utilized to limit the issues related to these aqueous phase toxins. Industrial effluents
and heavy metal pollution are a noteworthy biological issues due to their harmful
nature and inclination to aggregate in the food chain. They are nonbiodegradable in
nature and make aggregate in living bodies, a lot of them are cancer-causing agents.
Some poisonous metals include zinc, mercury, lead, chromium, cadmium, nickel,
and copper, which are of particular concern in curing industrial wastewaters (Patel
et al. 2018).
The industrial sources of frequently encountered heavy metals are hydroelectric
mining municipal wastewater, coal-fired power plants, pulp, and paper and refineries for mercury (Streets et al. 2018; Urgun-Demirtas et al. 2012); tanneries, electronic metal finishing mining operations, and plastics and etching for copper
(Al-Saydeh et al. 2017; Kazemipour et al. 2008); cadmium-containing folders, pigments, cadmium–nickel batteries, manufacturing of other metal, zinc ores, phosphate fertilizers, and nonferrous metal smelting for cadmium (Mortaheb et al.
2009); leaded gasoline, effluents from plastic, metal smelters, lead-based paint,
used batteries, microelectronics, and wood preservative-producing industries for
lead (Davis et al. 2001; Zhang et al. 2012); and coal mining and manufacturing,
sewage sludge, pharmaceutical products, steel production, waste combustion, insecticides, cosmetics, paints, and electroplating for zinc (Vongdala et al. 2019)
(Fig. 8.1).
Among all toxic metals, cadmium, arsenic, and mercury are viewed as more
lethal big three classification of overwhelming metals posing highest potential risk
to human being and environments (Gautam et al. 2014). Consequently, these substantial metals can make irreversible damage to human health and natural environment; furthermore, these lethal effluents cause serious damage to nearby ecosystem
if remain untreated (Jain and Jayaram 2010). There are different methods including
coagulation, adsorption, membrane separation, precipitation, filtration, electrolysis,
8 Agricultural Waste Absorbents for Heavy Metal Removal
and peanut hulls exhibited good results toward cadmium adsorption. Some other
adsorption studies conducted using activated carbon prepared coir pith, bagasse
pith, and dates and peanut shells. Their cadmium adsorption capacity was found to
be up to 98%. One study showed that tea-based adsorbent reduced almost 70% of
the hexavalent chromium into Cr(III). In short, agricultural waste can be used as
low-cost and most beneficial adsorbent for removal of heavy metals from aqueous media.
Keywords Environmental issues · Industrial effluents · Heavy metals · Adsorbent
· Nanocomposites · Agricultural waste · Chitosanyremediation
8.1 Introduction
Environmental contamination related to the substantial release of heavy metal in
wastewater coming from quick industrial development and urbanization is a worldwide concern. Therefore, different conventional treatment strategies have been utilized to limit the issues related to these aqueous phase toxins. Industrial effluents
and heavy metal pollution are a noteworthy biological issues due to their harmful
nature and inclination to aggregate in the food chain. They are nonbiodegradable in
nature and make aggregate in living bodies, a lot of them are cancer-causing agents.
Some poisonous metals include zinc, mercury, lead, chromium, cadmium, nickel,
and copper, which are of particular concern in curing industrial wastewaters (Patel
et al. 2018).
The industrial sources of frequently encountered heavy metals are hydroelectric
mining municipal wastewater, coal-fired power plants, pulp, and paper and refineries for mercury (Streets et al. 2018; Urgun-Demirtas et al. 2012); tanneries, electronic metal finishing mining operations, and plastics and etching for copper
(Al-Saydeh et al. 2017; Kazemipour et al. 2008); cadmium-containing folders, pigments, cadmium–nickel batteries, manufacturing of other metal, zinc ores, phosphate fertilizers, and nonferrous metal smelting for cadmium (Mortaheb et al.
2009); leaded gasoline, effluents from plastic, metal smelters, lead-based paint,
used batteries, microelectronics, and wood preservative-producing industries for
lead (Davis et al. 2001; Zhang et al. 2012); and coal mining and manufacturing,
sewage sludge, pharmaceutical products, steel production, waste combustion, insecticides, cosmetics, paints, and electroplating for zinc (Vongdala et al. 2019)
(Fig. 8.1).
Among all toxic metals, cadmium, arsenic, and mercury are viewed as more
lethal big three classification of overwhelming metals posing highest potential risk
to human being and environments (Gautam et al. 2014). Consequently, these substantial metals can make irreversible damage to human health and natural environment; furthermore, these lethal effluents cause serious damage to nearby ecosystem
if remain untreated (Jain and Jayaram 2010). There are different methods including
coagulation, adsorption, membrane separation, precipitation, filtration, electrolysis,
8 Agricultural Waste Absorbents for Heavy Metal Removal