BNCs HMI Optimum pH Maximum sorption capacity (mg·g-1 expect stated) IST/KNT models TMDs ( - ) References Magnetic layered double hydroxide/guar gum BNCs Cd (II) 10 258 LNR and PSO — [85 ] CS-lignin-titania NCs BB dye 5.8 15.8 FL and PSO — [84 ] Biodegradable hydrogel based on starch immobilized humic acid MB and Pb (II) 4.0-9.0 and 4.0-6.0 110 and 58 LNR and PSO Spontaneous and exothermal [86 ] Nickel sulphide incorporated polyacrylamide grafted gum karaya BNC hydrogel R-6G 7.0 1244.71 LNR and PSO Spontaneous and endothermic [87 ] CS-montmorillonite/polyaniline NCs MB — 111 Temkin and PSO — [88 ] CS and gum arabic NPs Cu (II) 10 303/344.8 LNR and PSO — [89 ] Alumina/CS (AlCS) composite Cr (VI) 3.0 8.62 D-R/PSO and intraparticle diffusion Spontaneous, endothermic, and randomness [90 ] Magnetic CLL/GO MB 6.0 70.03 LNR and PSO Spontaneous, exothermic, and favourable [91 ] CS/Ag BNCs Cu (II), Pb (II), and Cd (VI) 5.5-6.5 97, 88, and 89% — — [92 ] Zn-based magnetic zeolitic imidazolate framework BNCs using basil seed mucilage MB and Eriochrome Black T 10 and 2.0 9.09 and 13.21 FL/Elovich and PSO Spontaneous and endothermic [93 ] Partially hydrolysed polyacrylamide/CLL nanocrystal NC hydrogels MB 6.5 358.42 LNR and PSO — [94 ] Carboxylated CLL filters MB and Pb (II) 6.0 76.92 and 81.30 LNR — [95 ] BNCs of eggshell/Ag-Fe As (V), Pb (II), and Hg (II) — 17.7, 27.8, and 15.9 FL, Sip, and Redlich-Peterson/Elovich, PSO, and Elovich — [96 ] S. cerevisiae-AgNP BNCs Pb (II), Cu (II), Hg (II), Zn (II), Mn (II), Ni (II), Cr (VI), and As (V) 6.0-Cu (II) 91.75, 43.58, 19.72, 22.56, 12.47, 6.25, and 9.65% LNR and PSO for Cu (II) — [97 ] Cationic CLL hydrogels cross-linked by poly(ethylene glycol) Anionic dyes (AR13, AB92, and AR112) 2.0 440, 462, and 329 LNR and PSO — [98 ] Polyaniline/carboxymethyl CLL/TiO2 NCs CR 2.6 94.3 LNR, Hill, Sips, Redlich-Peterson, Khan, Toth, and Koble-Corrigan/PSO Spontaneous and endothermic [75 ] BPs (CS)/nanoclay composites Cu (II) and Ni (II) — 176 and 144 — — [99 ] Cationic starch/Na-montmorillonite BNCs Acid scarlet dye 7.4 43.7 Sips and PSO — [100 ] Gum ghatti and acrylic acid-based biodegradable hydrogels MB and RhB 7.0 909.09 and 819.67 LNR and PSO — [101 ] l-Methionine montmorillonite encapsulated guar gum-g-polyacrylonitrile copolymer hybrid NCs Pb (II) and Cu (II) 5.0 125 and 90.91 LNR and PSO Spontaneous, endothermic, and randomness [69 ] Hydrolysed polyacrylamide grafted xanthan gum and incorporated nanosilica NCs MB and MV 497.5 and 378.8 LNR and PSO Spontaneous, endothermic, and randomness [74 ] Chitin BNCs obtained from carb shells Pb (II), Cu (II), Ni (II), Cd (II), and Zn (II) 10 142, 166.6, 138.8, 100, and 142.85 FL and Temkin and PSO Spontaneous and endothermic [102 ] CS-based nanocomposite containing mesoporous nanosilica MCM-41 Pb (II) 6.0 125.85 LNR and PSO — [103 ] Magnetic layered double hydroxide/guar gum polymer BNCs Cr (VI) 6.0 101 LNR and PSO — [104 ] CS/Mg-Al-layered double hydroxide NCs Pb (II) and Cd (II) 3.0 333.3 and 140.8 LNR and PSO — [105 ] Hybrid BNCs from CLL nanowhisker and Mg/Al-CO3-LDH Cationic dyes (MB, MG, CV, JG, Fuc, and CR dyes) 13 21-27 PSO — [106 ] CS coated iron-oxide NCs As (III) 6.0 267.2 FL and PSO — [72 ] Hybrid BNCs from CLL and clay Drimarine yellow HF-3GL direct dye 2.0 48.9691 and 46.7548 Redlich-Peterson and PSO Spontaneous and endothermic [107 ] Functionalised mesoporous KCC-1 and CS-oleic acid Pb (II) 9.0 68 LNR and PSO Spontaneous, endothermic, and randomness [108 ] CS-coated bentonite As (V) — 1.47 LNR and PSO Nonspontaneous, endothermic, and randomness [109 ] Fe2 O3 -CS-cherry kernel shell pyrolytic charcoal composite beads Cr (VI) 2.0 47.576 LNR and PSO Spontaneous and endothermic [77 ] Starch-graft-acrylic acid/montmorillonite superabsorbent NC hydrogels Pb (II) and Cu (II) 4.0 — FL and PSO — [110 ] Xanthan gum/n-acetyl cysteine modified mica BNCs Pb (II), Cu (II), and Ni (II) 4.5 and 4.0 530.54, 177.2, and 51.48 LNR and PSO Spontaneous, endothermic, and with enhanced randomness [59 ] CS/polyvinyl alcohol/talc composite (CSPTC) CR, MO, Pb (II), and Cr (VI) 87%, 74%, and 380 and 200 mg/g — LNR/PSO — [111 ] Magnetic CS/GO composite Pb (II) 5.0 112.35 LNR/PSO — [112 ] Goethite/GO/CS NCs As (III) 3.0 289.42 FL and Sips and PSO Spontaneous and endothermic [113 ] CSGO As (III) 7.3 45 LNR and PSO Spontaneous and exothermic [114 ] Fe@polyethyleneimine As(III) 5.0 0.002 μ g/L — — [115 ]