Potential Use of Agro/Food Wastes as Biosorbents in the Removal of Heavy Metals

Abstract

The production of large quantities of agro/food wastes from food processing industries and the release of pollutants in the form of heavy metals from various metallurgical industries are the grave problems of the society as well as serious threats to the environment. It is estimated that approximately one–third of all food that is produced goes to waste, meaning thereby that nearly 1.3 billion tonnes of agro/food wastes are generated per year. This readily available and large amount waste can be utilized for the removal of toxic metals obtained from metallurgical industries by converting it into the adsorbents. For example, mango peel showed adsorption capacity of 68.92 mg/g in removing cadmium II ions. Similarly, coconut waste showed a higher adsorption capacity of 285 and 263 mg/g in removing cadmium and lead ion, respectively. Biosorption and bioaccumulation are recommended as novel, efficient, eco-friendly, and less costly alternative technologies over the conventional methods such as ion exchange, chemical precipitation, and membrane filtration, etc. for the removal of toxic metal ions. Because of the presence of metal-binding functional groups, the industrial by-products, agro-wastes and microbial biomass are considered as the potential biosorbents. Thus they can be used for the removal of toxic metal ions. This chapter highlights the available information and methods on utilizing the agro/food waste for the eradication of toxic and heavy metal ions. Furthermore, this chapter also focuses on the sorption mechanisms of different adsorbents as well as their adsorbing capacities.

Alleviating Heavy Metal Toxicity in Milk and Water through a Synergistic Approach of Absorption Technique and High Voltage Atmospheric Cold Plasma and Probable Rheological Changes

“…The use of bio-sorbents in heavy metal removal from wastewater has been reviewed in previous studies [ 63 ]. Hence, the present study utilized soybean husk as a bio-sorbent to absorb Pb and Cd from milk.…”

Valorization of Agri-Food Wastes as Sustainable Eco-Materials for Wastewater Treatment: Current State and New Perspectives

“…Today, there are plenty of treatment technologies being applied for diminishing water pollution and control of environmental quality [ 80 ]. Despite the economic features, such as high operational and maintenance costs, and also the generation of toxic sludge, the adsorption process is considered a better and low-cost option for water and wastewaters treatment.…”

“…Due to their polarity, these functional groups expose the capacity to link aquatic pollutants such as metals, dyes, organic compounds, usually by adsorption mechanism. Usually, the literature indicates the mass transfer process as the main step to remove pollutants by using agri-food wastes (as adsorbents), enhancing the accumulation capacity of adsorbent expressed as the pollutant quantity adsorbed, and residual pollutant concentration from solution [ 5 , 80 , 88 ]. An important aspect of adsorption efficiency is the mechanism of pollutant removal that depends on the physical and chemical characteristics of the adsorbent.…”

Adsorption kinetics and isotherms of binary metal ion aqueous solution using untreated venus shell

“…Some adsorbent provides high efficiency but is costly such as commercial activated carbon (CAC). Therefore, the reuse of agro/food wastes material as biosorbents for the removal of metal ions in wastewater is an emerging and potentially alternative method [ 16 ]. Biomaterials that are abundantly available as agricultural or food wastes have great potential to be used as a biosorbent because they are economical and environmentally friendly [ 17 , 18 , 19 ].…”