Synthesis of a Novel and Salt Sensitive Superabsorbent Hydrogel Using Soybean Dregs by UV-Irradiation

Abstract

A biomass based hydrogel soybean dregs-Poly(acrylic acid) (SD-PAA) was synthesized under UV radiation while using agricultural waste soybean dregs. Maximum absorption of SD-PAA is 3587 g·g−1 in distilled water and 302.0 g·g−1 in 150 mM NaCl aqueous solution. Moreover, the influence of granularity, salt solution, and ions in the solutions on water absorption is systematically studied. Sensitivity sequence of the hydrogel to cations was K+ < Na+ < NH4+ < Al3+ < Fe3+ < Mg2+ < Ca2+, and that to anions was PO43− > SO42− > Cl−. Moreover, the experimental results showed that SD-PAA water retention capability remained 37% after centrifugating for 60 min and 0.2% being dried at 60 °C for 70 h. Meanwhile, the swelling data agree well with the pseudo-second-order kinetic model and Fickian diffusion mechanism.

Thermally stable poly (acrylic acid‐acrylamide‐biomass‐fly ash) composites with improved temperature resistance and salt resistance

“…Therefore, the water absorption capacity of the composites decreases with the increase of the valence state of salt ions, and the water absorption capacity of the composites in NaCl solution is better than that in CaCl 2 solution. The results are consistent with those of Fan et al 43 At low salt concentration, the water absorption capacity of soybean dregs-poly (acrylic acid) decreased rapidly, and then decreased gently with the increase of salt concentration. The effect of monovalent cations on the water absorption of the composites is less than that of divalent cations.…”

“…The addition of cellulosic biomass and fly ash improved the water retention performance of the composites under high pressure. Fan et al 43 (acrylic acid). The water retention rate of the material decreased with time under the conditions of high temperature and high pressure.…”

Preparation and Applications of Salt-Resistant Superabsorbent Poly (Acrylic Acid-Acrylamide/Fly Ash) Composite

“…There are mainly two kinds of superabsorbent dehydration: heated evaporation and pressure dehydration (that are caused by pressure, centrifugal force, etc.) [ 29 ]. In practical application, the environment where the superabsorbent used is usually under pressure or high temperature.…”

Preparation and anti‐evaporation properties of organic–inorganic superabsorbent based on Tragacanth gum and clay

“…Thus, due to its optimal water retention and water absorption, SAP can be used as a water storage material in the arid desert environments 7 . In addition, SAP materials can also be applied in biomedical engineering, 8 agriculture and environmental protection, 9 health products, industrial dehydration, construction, etc 10 …”

“…7 In addition, SAP materials can also be applied in biomedical engineering, 8 agriculture and environmental protection, 9 health products, industrial dehydration, construction, etc. 10 Tragacanth gum (GT) is a complex, acidic and highly branched anionic polysaccharide 11 containing a variety of carbohydrates, such as L-arabinose, D-galactose, D-xylose, L-fucose, L-Rhamnose and D-galacturonic acid. [12][13] The GT structure contains primary and secondary hydroxyl, carboxylic acid and epoxy groups, which provide ideal locations for the reactions with the reagents containing different functional groups.…”