TITLE:
Synthesis of Modified Walnut Shell Biochar and Its Performance of Cadmium Adsorption
AUTHORS:
Jiankun Chen, Jianan Wang
KEYWORDS:
Biochar, Wastewater, Cadmium, Environmental Pollution, Walnut Shell
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.11 No.9,
September
27,
2023
ABSTRACT: Biochar is a functional and
environmentally friendly material mainly made from by-products of industrial and agricultural
production as raw material, which is cracked at high temperatures and slow speeds. The preparation of biochar requires the
thermochemical conversion of biomass in an oxygen-restricted environment.
Different raw materials and preparation processes result in biochar with
different internal structures and biofunctional groups, which often have
different properties. Adsorption of heavy metal pollutants is one of the main research directions for biochar application,
and there are still areas that can be
improved in the current research for biochar for treating heavy metal wastewater. In this study, we take the
treatment of cadmium-containing wastewater as an example, walnut shell biochar
(WSBC) as a carrier, iron(VI) compounds
as a modifying reagent, and test the performance of cadmium-containing wastewater treatment using simulated
cadmium-containing wastewater by adjusting the pyrolysis process and
modification method at the same time to find
the optimal experimental scheme, and give a reasonable theoretical explanation in relation to the results of the
characterization tests, such as SEM,
FT-IR, and so on. The characterized results show that iron(VI) compound
(K2FeO4)-modified WSBC has a significant ability to remove
cadmium contamination in the wastewater (remove 96.62% of cadmium in 1 minute),
and its structure is different from other iron compound-modified ones. The aim of this study is to improve the
efficiency of cadmium adsorption by specific types of biochar, while
realizing the whole process as environmentally friendly as possible.