Synthesis of clamshell derived Ca(OH)2 nano-particles via simple surfactant-hydration treatment

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2015-02, Vol.262, p.1043-1051
• Main Authors: Asikin-Mijan, N., Taufiq-Yap, Y.H., Lee, H.V.
• Format: Article
• Language: English
• Subjects: Calcium hydroxide; Catalyst; Clamshell; Nanoparticles; Surfactant
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2014.10.069

Schematic diagram for synthesis of clamshell derived Ca(OH)2 nano-particles via surfactant-hydration treatment. [Display omitted] •Hydration-surfactant treatment of clamshell to produce green nano-Ca(OH)2.•Nano-Ca(OH)2 derived from clamshell render superior basicity than CS-CaO.•Nano-structured of Ca(OH)2 was studied by different surfactants (EG, DE & CTAB).•Treated catalysts render comparable properties as commercial Ca(OH)2.•EG rendered best dispersion effect to reduce particle sizes of nano-Ca(OH)2. Recently, calcium hydroxide (Ca(OH)2) nanoparticles derived from calcium oxide (CaO) has been getting attention from researchers as heterogeneous catalyst for several chemical reaction such as: transesterification, chemisorbents for toxic gases and cracking-decarboxylation process. Ca(OH)2 in nano-crystal structures exhibit superior characteristics which enhance the reaction. In Malaysia, clam species (Meretrix meretrix) are abundantly available in backwater and estuaries along the coast. It is a green material that composed of at least 95% of calcium for CaO production. In the present study, a green solid base Ca(OH)2 nanoparticles was prepared using waste clamshell (M.meretrix) via low cost wet-chemical route. The effects of wet-surfactant treatments (ethylene glycol (EG), diethyl ether (DE) and N-Cetyl-N,N,N-trimethylammonium bromide (CTAB)) on clamshell derived CaO (CS-CaO) were examined. Furthermore, the physicochemical properties of CS-CaO and surfactant treated Ca(OH)2 were analyzed using X-ray fluorescence spectrometer (XRF), X-ray diffraction spectroscopy (XRD), fourier transform spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET) technique, temperature program desorption of carbon dioxide (TPD-CO2), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The results showed that surfactant treatments are capable of enhancing properties of clamshell derived nano-Ca(OH)2 materials such as particle sizes, surface area and basicity. Among the surfactants, EG rendered the most significant effect on the clamshell-derived material, with surface area of 78.38m2g−1, basicity of 4658.8μmol/g and nanoparticle sizes at 25–42nm.