Recent investigations have revealed the harmful health effects of elevated calcium levels in drinking water. Chemically activated biochar is the most popular option for low-cost cation adsorption. However, most of these chemicals are hardly available for rural communities, corrosive, and difficult to handle by unskilled personnel. This study aimed to determine the ability of natural coconut vinegar, a common mild acid, to activate Trema orientalis wood biochar pyrolyzed at 300ºC (BC) as a facile, safe, and low-cost approach for aqueous calcium ion (Ca 2+ ) removal. Column tests showed a two-fold increase of Ca 2+ adsorption capacity and a ten-fold increase of Ca 2+ retaining capacity of BC after activation with vinegar. The isotherm results were well correlated with the Langmuir model. The maximum Langmuir adsorption of the activated biochar (BC-A) was 9.96 mg/g. Ca 2+ amount was determined using flame photometry. EDX analysis showed that the O/C ratio of BC increased from 0.07 to 0.13 after activation. FTIR and wettability studies showed increased oxygenated functional groups on the BC-A surface. The authors suggest a possible acid-catalyzed hydration of the C-O-C bridges of the biochar, introducing new hydroxyl/carbonyl/ester/carboxylic/lactone groups to the biochar surface due to the vinegar activation, enhancing Ca 2+ adsorption through chemisorption.
A positive correlation has been reported recently among the number of Chronic Kidney Disease of Unknown Etiology (CKDu) patients and the levels of groundwater hardness.Hence, the need for a low cost and a simple domestic process to reduce the hardness of potable water is identified to improve living standards of low-income communities in these disease affected areas. Biochar has emerged as a low cost adsorbent for water treatment, because of its abundance and cost-effectiveness. This study was aimed to evaluate the ability of natural coconut vinegar, in activating Leucaena leucocephala wood biochar to be used in calcium ion (Ca 2+ ) removal from potable water. Column tests showed a 1.7 fold increase of Ca 2+ adsorption capacity and a 7 fold increase of Ca 2+ retaining capacity upon the vinegar treatment. Batch studies matched with both Langmuir (R 2 = 0.9761) and Freundlich (R 2 = 0.9785) isotherm models. Ca 2+ amount in solutions were measured using flame photometry. Ca 2+ adsorption capacities of raw biochar and activated biochar determined by column tests ranged from 3.10-3.82 mg/g and 5.27-6.68 mg/g respectively while Ca 2+ retaining capacities ranged from 0.16-0.22 mg/g and 1.28-1.4 mg/g respectively. Fourier transform infrared spectra, suggests hydration of the C-O-C bridges of the biochar surface introducing new -O-H groups and possible introduction of carbonyl/ ester/carboxylic functional groups to the biochar surface upon vinegar treatment.According to scanning electron microscopy porosity of the biochar remained stable after the vinegar treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.