Cadmium Removal by Adsorption on Biochars Derived from Wood Industry and Craft Beer Production Wastes

Abstract

Cadmium pollution is a serious environmental issue that has an impact on both theecosystem and human health. As a result, its removal from water is essential. Agro-industrialwastes are suggested as a sustainable adsorbent option, as they are among the most readily availablerenewable sources worldwide. Biochar is a carbonized biomass that has been shown to be a viableand novel adsorbent. This article compares the results of cadmium adsorption on biochars derivedfrom wood industry and craft beer production wastes. Biochars were characterized before andafter adsorption. Batch adsorption results of 0.18 mmol/L Cd(II) concentration solutions indicatedadsorption percentages (A%) of 99.7% and 92.2% for sawdust biochar and barley biochar, respectively.For this cadmium concentration, the sawdust biochar presented an adsorption capacity (qm) of0.0172 mmol/L, while the barley biochar presented a value of 0.0159 mmol/L. The influence ofinitial Cd(II) concentration on single and multimetal solutions was studied, and a decrease in Cd(II)adsorption on sawdust biochar was observed in the presence of Ni(II) and Zn(II). The Freundlichisotherm model was found to be the best fit to the data for Cd(II) adsorption isotherms on bothbiochars. According to the results of this article, sawdust biochar has the best performance as anadsorbent and can be safely disposed of in building bricks at the end of its useful life.