The preparation and utilization of the cationic sorbent based on the surfactant modified bottle gourd shell

Abstract

The surface of the bottle gourd shell (BGS), a solid agricultural residue of Lagenaria vulgaris Ser. was chemically modified using a cationic surfactant, hexadecyltrimethylammonium chloride (HTAC). The success of the modification was confirmed by FTIR spectroscopy. Chemical characterization of the lignocellulosic BGS biomass and the surfactant modified bottle gourd shell (MBGS) was carried out using the compositional and elemental analysis. The amount of surfactant sorbed on the BGS surface was measured as a function of the surfactant bulk concentration. Sorption isotherms were used to verify self-assembly models of cationic surfactant sorption onto oppositely charged MBGS substrates. The shape of sorption isotherms was applied to describe the behavior of the surfactant/BGS system. The surfactant modified shell was tested as a sorbent for the removal of phosphate and nitrate from contaminated aqueous solutions. The sorption of anionic pollutants on MBGS was performed in a series of batch sorption experiments at 20 o C. It was found that the MBGS yielded sorption efficiency was 40% for phosphate and 22% for nitrate. The sorption mechanism involving the ion exchange might be responsible for the uptake of anions. The morphology and surface properties of the MBGS sorbent before and after sorption of anionic pollutants were analyzed by SEM methods. Compared to other non-surfactant sorbents, the advantage of MBGS as a sorbent is that it can be used for the removal of anionic pollutants not only from aqueous solutions but also from the emulsified oil wastewater or nonpolar effluents.

Development and characterisation of miscellaneous cationic sorbents based on lignocellulosic gourd shell

“…The high values of reaction efficiency (RE 78.91-97.39%) and product yield (97.4-97.9%) indicate maximum utilization of the reagent amount. However, the small degree of substitution and the predicted two-layer mechanism suggest that the obtained data may not be relevant for evaluating the sorption efficiency of anionic species from solution [50]. This can be explained by the fact that at least half of the total amount of bound surfactants are engaged in the interaction with active biomass centers, while the rest are available for the sorption process of anionic contaminants (Figure 3).…”

“…However, it should be noted that these bands, together with a deformation vibration band of OH group (in plane) at 1423 cm -1 and a wide band of the vibration of the cellulose ester group at 1260 cm -1 , are correlated with the crystalline cellulose structure [43]. Thus, the apparently small changes in band intensity indicate a 8(2) (2019) [46][47][48][49][50][51][52][53][54][55][56][57] proportional change in the fraction of the crystalline to amorphous form of certain cellulose areas in the treated sample, which favors more efficient sorbent synthesis based on this precursor.…”

“…Mechanism of formation of monolayer (a) and bilayer (b) complex aggregates of CTAC surfactants on the surface of ligno-cellulosic biomass[50] …”

“…Model of anionic species sorption from aqueous solution on LVAT biomass modified by CTAC surfactant[50] …”

The biosorption potential of modified bottle gourd shell for phosphate: Equilibrium, kinetic and thermodynamic studies

“…The dried fruit shell, as a biocompatible natural material of hard and porous structure, is an exceptionally valuable agricultural residue for making potentially attractive biosorbents of different functionalities. This is due to the large amount of easily available hydroxyl groups existing in the cellulose, hemicelluloses, and lignin, which can easily make a series of chemical reactions, such as condensation, etherification and copolymerization [13,14]. The use of LVS as an efficient and inexpensive alternative biosorbent in natural and activated forms (activated carbon) for the removal of some toxic metal ions from wastewater (Pb 2+ , Cd 2+ , Zn 2+ , Cu 2+ and Ni 2+ ) [7,15,16], and other cationic pollutants, such as dyes [17] or pharmaceuticals [18], was examined.…”