A Review on Magnetic Nanobiochar with Their Use in Environmental Remediation and High-Value Applications

Abstract

Magnetic nanobiochar (MNBC) is a sort of nanobiochar that has been enhanced with magnetic qualities. MNBC is made from a variety of feedstocks, including wood chips, agricultural waste, municipal sludge, animal manure, and other organic waste. These feedstocks are pyrolyzed at various temperatures to produce biochar, which is then mixed with magnetic precursors to create MNBC. Crystallinity, high porosity, specific surface area, and great catalytic activity are a few of the dynamic properties of MNBC. The major purpose of this review paper is to characterize MNBC, using the various biochar synthesis methods and how bulk biochar is converted into MNBC with their high-value applications discussed here.

Recent trends and economic significance of modified/functionalized biochars for remediation of environmental pollutants

“…Jin et al 55 observed that the cobalt-doped biochar of bamboo showed higher pore volume and surface area than the un-doped adsorbent, which led to greater chromium hexavalent removal capacity. Similarly, a substantial increase in pore volume and surface area was also found with an enhancement of Fe quantity on coated biochar 50 . Loading of surfactant for carbon nanotube dispersion during the preparation of carbon nanotube doped-biochar resulted in a greatly higher sorption capacity of carbon nanotube-loaded biochar for pollutants (lead and sulfapyridine) than without surfactant owing to the magnificent distribution and dispersion of carbon nanotube on the adsorbent surface 11 .…”

“…Applying chitosan as a modifying agent, established amine functionalities on the surface of biochar to enhance its adsorption capacity and affinity to inorganic pollutants 49 . Chitosan loading on the surface of biochar can also enhance its effectiveness as a soil rectification, as well as chitosan-loaded adsorbent, may be applied as an efficient, eco-friendly, and low-cost adsorbent to decontaminate the pollutants from the environment 50 . H 2 O 2 -modified biochar derived from peanut hull surface enhanced oxygen-enrich functional groups, particularly the carboxyl group which accelerates the metals removal capacity and affinity of adsorbent 9 .…”

“…Lyu et al 109 observed that the surface complexation between hydroxyl groups and Pb (II) provided via montmorillonite stimulated the sorption efficiency. Sonowal et al 50 produced porous magnesium oxide-doped biochar with thick flakes of polycrystalline magnesium oxide from several feedstock biomasses such as peanut shells, sugar beet, cottonwood, sugarcane bagasse, and pinewoods. These biomasses were dipped in magnesium dichloride solutions and ensued dry-mixture of magnesium dichloride incorporated biomass was heated at 10 °C min −1 at 600 °C.…”

Sustainable Technological Applications of Green Carbon Materials

“…Although biochar research in agriculture is a well-established area, its nanosized fraction, nanobiochar, is in the early stage of scientific research. Nanobiochar is being proposed for environmental remediation, although the mechanism of action is poorly understood [53][54][55][56]. Nanobiochar has superior physicochemical properties to biochar, such as high catalytic activity, a large SSA, and high environmental mobility [53].…”

“…Nanobiochar has superior physicochemical properties to biochar, such as high catalytic activity, a large SSA, and high environmental mobility [53]. The main applications of nanobiochar in environmental treatment technologies are in pollutant removal, like heavy metals, toxic organic substances, and emerging pollutants, via adsorption mechanisms like ion exchange, complexation, precipitation, electrostatic interaction, and physical adsorption [53][54][55]. As discussed above, the biochar's structure and properties depend on the raw materials and technological characteristics of the pyrolysis process, and the same is naturally observed for nanobiochar [54,55].…”