The adsorption of hydrogen on structurally well defined PdAu-Pd(111) monolayer surface alloys was investigated in a combined experimental and theoretical study, aiming at a quantitative understanding of the adsorption and desorption properties of individual PdAu nanostructures. Combining the structural information obtained by high resolution scanning tunneling microscopy (STM), in particular on...

To investigate the relationship between Cr(VI) adsorption mechanisms and physio-chemical properties of biochar, ramie residues were oxygen-limited pyrolyzed under temperature varying from 300 to 600°C. Batch adsorption experiments indicated that higher pyrolysis temperature limits Cr(VI) sorption in terms of capacity and affinity due to a higher aromatic structure and fewer polar functional gro...

The garden grass (GG) was firstly used to remove copper(II) from water as bioadsorbent. From the results of characterisation, the GG had the merits of high specific surface area, significant adsorption sites and functional groups. Copper-adsorption significantly depends on the initial copper concentrations, contact time, pH, adsorbent doses, particle sizes and temperature. The positive values o...

The plant powder of Jaswand (Hibiscus rosa-Sinensis) were activated with sulphuric acid and used as low cost easily available and renewable biological adsorbent for the removal of acid dyes (acid blue, acid red and malachite green) from aqueous solution. Batch experiments were carried out for adsorption kinetics and isotherms. Operating variable studied were pH, temperature, adsorbent dose, ini...

The preferential blocking of the interior adsorption sites of single walled carbon nanotubes (SWNTs) by n-nonane is demonstrated. Following adsorption of n-nonane and evacuation for 24 h at 323 K, it was found that interior sites with diameters less than 14 Å remained filled with n-nonane, blocking the physical adsorption of N2 on these sites at 77.3 K. We demonstrate that ‘‘nonane blocking’’ i...

The statistical rate theory (SRT) fundamental kinetic equation for the Langmuir model of adsorption reveals some features which are difficult to understand. These are the infinitely high adsorption rate for zero coverage limit, infinitely high desorption rate at full saturation of the surface and dependence of the desorption rate on the adsorbate pressure. These features do not allow for a corr...

The adsorption of 1-naphthol (NAP) in aqueous solution was investigated using unmodified and modified diatomite at different temperature, pH, adsorbent mass and contact time. The adsorption capacity of the modified diatomite significantly improved (about 2 times at 298 K) compared to the unmodified diatomite. The adsorption showed a good fit with the Langmuir model. The further data analysis de...

Adsorption behavior of unburned carbons from fly ash has been investigated in this study. Batch tests and column test were carried out for several unburned carbon samples from various ash sources and processing schemes. Adsorption isotherms have been obtained from these tests. Results show that the unburned carbons have equal or better adsorption capacity for elemental mercury comparing with so...