An updated review on boron removal from water through adsorption processes

Abstract

Boron is an essential micronutrient that has raised much interest, given the narrow balance between its necessity and toxicity. Both natural and anthropogenic emissions of boron into water sources can eventually deteriorate water quality and endanger the ecosystem. In this review, we first present a general outline of the importance of boron, boron chemistry in water, boron contamination, and its consequences followed by the recent progress in boron removal methods based on adsorption. The adsorbents for deboronation can generally be classified based on the functional groups present; chelating groups, metal oxides, and layered double hydroxides. To comprehensively address these adsorption methods, a detailed discussion on the reaction mechanism of each system is done followed by a summary of the progress in the field during the past 5 years. Finally, some characterization techniques used in deboronation studies and suggestions for future research and applications together with possible improvements to the existing systems are presented. Graphical abstract

Sorption–desorption of some transition metals, boron and sulphur in a multi-ionic system onto phyto-biochars prepared at two pyrolysis temperatures

“…The intensity of sorption (1/ n ) values for all transition metals was less than unity indicating the involvement of heterogeneous sites only whereas for B sorption, the 1/ n values were invariably greater than unity plausibly indicating a case of cooperative adsorption. 45 A similar case was also noted for S sorption, especially for phyto-biochars pyrolyzed at 450 °C. The highest desorption capacity () for Zn (61.752 mmol kg −1 ), Fe (346.669 mmol kg −1 ) and Mn (80.591 mmol kg −1 ) was recorded with W450 while the highest for Cu (68.727 mmol kg −1 ), B (90.786 mmol kg −1 ) and S (1698.825 mmol kg −1 ) was observed with L450.…”

Boron and lithium behaviour in river waters under semiarid climatic conditions

“…This could reflect the known strong Li affinity for Fe-oxyhydroxide surfaces (Wimpenny et al, 2010a) and the lack of reactivity of B species on the positively charged surface of Fe-oxyhydroxides (Kosmulski, 2002(Kosmulski, , 2016. Finally, the B/Li ratio in the detrital sediment fraction roughly corresponds to the B/Li crustal value, while both dissolved B and Li species are not partitioned onto surfaces of detrital minerals during authigenic processes (Bhagyaraj et al, 2021), as observed in Fig. 5D.…”

Kinetics and isotherm studies for the adsorption of boron from water using titanium dioxide

“…A key aspect influencing the removal of boron from water is its pH. Several investigators [24][25][26][27] have studied the effect of pH; optimum pH appears to be in the range of 8-10, where boron is present in negatively charged ionic form and borates predominate. B(OH) 3 prevails at lower pH, while B(OH) 4 prevails at pH greater than 8.…”