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The use of biomass residues from agricultural processes for the production of cheap and competitive activated carbon (AC) is an excellent option to minimize the costs of existing procedures to remove dyes from wastewater. In this study, the potential use of AC obtained from peanut hulls and rice husks for adsorption of Cibacron Yellow F-4G (CYF-4G) is examined. The activated peanut hull (PHAC) and rice husk (RHAC) were characterized by TGA, FTIR, BET and elemental analysis. The effects of different process variables as well as the dose of adsorbent, dye concentration and pH were evaluated. A decrease in amount of dye adsorbed per unit adsorbent mass was observed when increasing CYF-4G concentration. The results showed an optimal dye adsorption value at a pH of 2.0. The adsorption kinetics of CYF-4G are governed by the pseudo-second-order model. In addition, adsorption fits the Langmuir isotherm better than Freundlich’s. Adsorption capacities of AC prepared from agricultural waste show that PHAC performs better than RHAC to remove CYF-4G.

Two different heat treatments for MDF, microwave assisted pyrolysis (MWP) and conventional pyrolysis (CPS), are investigated. The influence of different microwave absorbers (activated carbon (AC) and K2CO3) and different microwave powers in MWP and different temperatures in CPS on the characteristics of biochar is reviewed. Morphology and chemical properties of the obtained biochars are evaluated comparing biochar yield, ultimate analysis, proximate analysis, biochar stability test, FTIR spectroscopy and solid-state 13C CP/MAS NMR spectroscopy. The resulting biochars of both processes are compared to find the best production method. An increasing microwave power without the use of MWA, leads to a higher degree of aromaticity. The addition of increasing amounts of AC at low microwave power (300 W) leads to higher pyrolysis temperatures and more aromatic biochars. At 400 W a more aromatic biochar with a more open surface is achieved compared to 300 W. However, the addition of an increasing amount of AC as a MWA at 400 W induces a lower pyrolysis temperature with increasing biochar yields and decreasing aromaticity. K2CO3 is more effective as a MWA and produces more aromatic biochar at lower microwave power than when using AC. In general MWP yields a biochar with a higher degree of aromaticity at lower temperatures than CPS. Both CPS and MWP are viable options for transforming MDF into a value added biochar. This work was supported byAgentschap Innoveren en Ondernemen (VLAIO) [BM20160604]; European Institute of Technology (EIT); and Research Foundation Flanders (postdoctoral fellowship D. Vandamme [FWO - 12D8914N]). Koen Van Vinckenroye for support with the 13C solid state NMR measurements Elsy Thijssen and Martine Vanhamel for FTIR measurements This work was supported byAgentschap Innoveren en Ondernemen (VLAIO) [BM20160604]; European Institute of Technology (EIT); and Research Foundation Flanders (postdoctoral fellowship D. Vandamme [FWO – 12D8914N]).

The removal of Ibuprofen was investigated by activated carbon impregnated with TiO2. Emphasis was given on the effect of different parameters, such as composite type, initial Ibuprofen concentration (5–25 mg/L), temperature (22–28 °C) and pH (acidic and alkaline solution). The experiment was carried out in a self-made tubular flow reactor, with one 15 W monochromatic UV lamp (254 nm). The composite AC90T10 gives the highest removal degree of 92% of Ibuprofen solution under UV light within 4 h, due to synergy of adsorption and photodegradation. It was found that weight ratio of composite/Ibuprofen has limited effect on the removal degree within the concentration range (5–25 mg/L), but reaction time under UV light (4 h) and pH (acidic solution) are very important. The kinetic experimental data obtained at pH 4.3 at 25 °C on different composites were fitted to pseudo-first, pseudo-second and Elovich models, obtaining a high accuracy based on R2 values. From the results, composites of granular activated carbon and TiO2 can enhance removal of Ibuprofen effectively, making recycle process much easier and less costly, which can be a promising method in future water treatment.

Adsorption of Ni(II) on low cost activated carbon (AC) from spent coffee (SAC) and coffee husk (HAC) has been studied. Porous textures of adsorbents were characterized by N2 and CO2 sorption measurements. Batch adsorption experiments were performed as a function of adsorbent dose, Ni(II)-concentration and pH. Adsorption of Ni(II) was evaluated using different adsorption isotherm models (Langmuir, Freundlich, Monolayer Model for Single-Compound Adsorption and Dubinin – Radushkevich) and thermodynamics and kinetics parameters were determined. Both adsorbents show high affinity for Ni(II), however both the surface area and the pore size of the ACs do not seem to be the determining factor in the adsorption process. These ACs are microporous in nature. In contrast, the higher oxygen amount associated to the mineral matter as K2O and carbon functionalities corresponding with O H in HAC are determining for the Ni-ion adsorption process and multi-ion anchorage mechanism. In addition, the exchange of potassium present in the ACs improves the Ni(II) adsorption process. Thermodynamics and kinetics evidence a fast and endothermic adsorption process. The maximum adsorption capacity using the Langmuir isotherm model was found to be 57.14 mg/g and 51.91 mg/g for HAC and SAC, respectively. The sorption efficiency was higher for HAC as adsorbent. At low concentrations of Ni(II) (30 mg/L) and higher temperatures (308–328 K), removals >94% were measured for HAC, achieving safe discharge concentration values.

Spectrophotometric measurements applied on saturated granular activated carbons have been barely explored. Although Nuclear Magnetic Resonance (NMR) relaxation studies proved to be suitable to explore pore characteristics in different porous materials, characterization of granular activated carbons used in rum production have not been addressed yet. In this work, the feasibility of using NMR relaxometry and colorimetry in order to characterize the exhaustion degree of granular activated carbon (GAC) from a target rum “filter” is evaluated. Colorimetric measurements and the transverse NMR relaxation time distribution have been correlated with the amount of adsorbed organic compounds on these GAC. Samples from eight consecutive GAC layers of the rum filter have been assessed. The exhaustion profile for the rum “filter” is correlated with the colorimetric results, the 1H NMR T2-relaxometry measurements, the TD-GC/MS chromatograms and the CHNS-O elemental analysis. The proposed methods are not only of general use in GAC characterization but open possibilities for the rum producers to improve the management and economical use of the activated carbon at industrial scale.

The removal of Ibuprofen was investigated by activated carbon impregnated with TiO

The Youth Division of the Royal Flemish Chemical Society (Jong-KVCV) has over 300 members, accounting for approx. 45 % of the total society. Christophe De Bie (President of KVCV), Jens Maggen (President of the Jong-KVCV), Lucia Habets Vicepresident Jong-KVCV), Kersten Van Langenhove (Secretary Jong-KVCV), Karel Haesevoets, Geert-Jan Graulus, and Niels Van Herck talked with Vera Koester for ChemViews Magazine about the work and aims of the Jong-KVCV as well as their personal motivations and ideas for the future.

Band engineered Si/O superlattices are promising channel materials for ultimately scaled complementary metal oxide semiconductor devices. Theoretical calculations have indicated that insertion of O monolayers into Si lattice creates anisotropy in the Si band structure with an enhanced carrier mobility in the channel direction. However, the experimental demonstration of such superlattices is not straightforward, as it requires processes for the deposition of a monolayer of O on Si, and to continue the Si epitaxy thereon. In this work, we investigate processes for the fabrication of Si/O superlattices using the chemical vapor deposition technique. Ozone is used for the O deposition with control of the deposited O content at the monolayer level. The SiH 4 based Si deposition is performed at low temperatures (500 °C–550 °C) in order to obtain a confined O monolayer in the Si superlattice. Si deposited on O layer of 1.2 O monolayers is completely amorphous. This indicates that this O layer is extremely uniform as it prevents any epitaxial ordering with the substrate. Reducing the O content to 0.9 O monolayers in combination with a slower Si deposition favors epitaxial ordering of Si on O/Si. Finally a defect free Si epitaxy is demonstrated on the O monolayer. Such ordering of epitaxial Si on the O layer provides a promising outlook for the growth of superlattices.

Crystalline superlattices consisting of alternating periods of Si layers and O-atomic layers are potential new channel materials for scaled CMOS devices. In this letter, we investigate Chemical Vapor Deposition (CVD) for the controlled deposition of O-atoms with O-3 as precursor on Si(100) substrates and Si epitaxy on the O-layer. The O-3 reaction at 50 degrees C on the H-terminated Si results in the formation of Si-OH and/or Si-O-Si-H surface species with monolayer O-content. Defect-free epitaxial growth of Si on an O-layer containing 6.4E+14 O-atoms/cm(2) is achieved from SiH4 at 500 degrees C. (C) 2013 The Electrochemical Society. All rights reserved.

Pig manure results in the release of NH3, NOx, volatile organic compounds and odour nuisance. Pyrolysis of dried pig manure can be considered as an economical viable approach converting this agricultural waste into value added products. The produced amendment biochar can be used as a slow release fertilizer with high concentration of N, K and P and has beneficial effects as carbon sequester and improver of soil quality and crop productivity. It is proved that a 2 wt.% blending of biochar with a poor soil affects positively plant growth and crops (dwarf beans), and worm (Eisenia fetida) survival and production. Additional, available heavy metals are immobilised in the biochar and not leachable. The resulting biochar therefore offers prospects as low cost, slow release soil conditioner and fertiliser for a long term effect. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors