Biomaterial Database

Humic acid-inspired hybrid materials as heavy metal absorbents. 2010

Panagiota Stathi, and Yiannis Deligiannakis

Laboratory of Physical Chemistry, Department of Environmental and Natural Resources Management, University of Ioannina, Seferi 2, 30100 Agrinio, Greece.

Three SiO(2)-based materials were prepared via covalent immobilization of carboxyl groups (COOH), phenolic groups (GA), or humic acid on an SiO(2) surface. Their sorbing properties were evaluated for removal of heavy metals (Pb(2+), Cd(2+), Cu(2+), Zn(2+), and Mg(2+)) from aqueous solution. The data show a significant improvement for metal uptake, compared to unmodified silica that can be attributed to the adsorption of metals to the deprotonated form of functional groups (COOH, GA, HA). The metal-uptake capacity of the SiO(2)-HA material was 10 times higher that those of the other two materials. The present data provide direct experimental proof that HA can be viewed and modeled as a combination of -COO and R-OH functional groups.

UI	MeSH Term	Description	Entries
D010316	Particle Size	Relating to the size of solids.	Particle Sizes,Size, Particle,Sizes, Particle
D006812	Humic Substances	Organic matter in a state of advanced decay, after passing through the stages of COMPOST and PEAT and before becoming lignite (COAL). It is composed of a heterogenous mixture of compounds including phenolic radicals and acids that polymerize and are not easily separated nor analyzed. (E.A. Ghabbour & G. Davies, eds. Humic Substances, 2001).	Humic Acid,Humic Acids,Humic Substance,Sodium Huminate,Acid, Humic,Acids, Humic,Huminate, Sodium,Substance, Humic,Substances, Humic
D000327	Adsorption	The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.	Adsorptions
D012822	Silicon Dioxide	Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.	Silica,Aerosil,Aerosil 380,Cristobalite,Quso G-32,Quso G32,Tridymite,380, Aerosil,Dioxide, Silicon,G32, Quso,Quso G 32
D012996	Solutions	The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Solution
D013499	Surface Properties	Characteristics or attributes of the outer boundaries of objects, including molecules.	Properties, Surface,Property, Surface,Surface Property
D014867	Water	A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Hydrogen Oxide
D019216	Metals, Heavy	Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)	Heavy Metal,Heavy Metals,Metal, Heavy