Krystyna Hoffmann, Józef Hoffmann, Marta Huculak-Mączka and Jakub Skut
Investigation of applying calcium oxide for the removal of bitter substances from hop wastes
Utilization of brewery wastes is one of the solutions for the production of the fodder supplements containing biogenic nutrients. The condition of such application is to meet the requirements included in the regulations regarding animal feeding, particularly removing a bitter taste. The aim of the performed investigations was the removal of bitter acids from the post-extraction hop waste using the calcium oxide addition. For the examination hop wastes obtained as a by-product from the CO2 plant extraction in supercritical conditions, were applied. Physicochemical properties of the waste samples collected for the investigations were determined by applying the available standard analytical techniques. The analyses of the determination of bitter acids were carried out by the high performance liquid chromatography method. During the experiments very good effects of bitter acids removal from hop wastes, were obtained by using CaO suspensions in water. The investigations on the influence of the CaO concentration in suspension on the efficiency of bitter acids removal indicate the possibility of applying suspensions by 2 wt% for this purpose.
In this paper, Co,Ce/Ca10(PO4)6(OH)2 catalysts with various cobalt loadings for steam reforming of ethanol (SRE) were prepared by microwave-assisted hydrothermal and sol-gel methods, and characterized by XRD, TEM, TPR-H2, N2 adsorption-desorption measurements and cyclohexanol (CHOL) decomposition tests. High ethanol conversion (close to 100%) was obtained for the catalysts prepared by both methods but these ones prepared under hydrothermal conditions (HAp-H) ensured higher hydrogen yield (3.49 mol H2/mol C2H5OH) as well as higher amount of hydrogen formed (up to 70%) under reaction conditions. The superior performance of 5Co,10Ce/HAp-H catalyst is thought to be due to a combination of factors, including increased reducibility and oxygen mobility, higher density of basic sites on its surface, and improved textural properties. The results also show a significant effect of cobalt loading on catalysts efficiency in hydrogen production: the higher H2 yield exhibit catalysts with lower cobalt content, regardless of the used synthesis method.
Food industry waste composting in a rotational reactor
The permanently rising costs of food industry waste management create a real necessity for searching for new economical and environmentally friendly technologies with which such waste can be utilized. The purpose of this study was an evaluation of waste composting using rotational reactor technology with further use of the resultant product as a fertilizer. In order to conduct the research, a rotational reactor was designed and constructed. For the composting process, such waste materials as meat and bone pulp, past its sell-by date dairy and bakery products, sawdust, poultry and cattle manure, were used. The composition of the composted masses was chosen so that their approximate C:N:P proportions and consistency were appropriate for the growth of biodegradating micro-organisms. The efficiency of the presented technology was evaluated based on the inactivation of selected strains of bacteria and the eggs of invasive parasites. The products obtained were tested by the Institute of Soil Science and Plant Cultivation in Puławy with regard to its possible environmental usage.
The study was aimed at investigating the effect of the Fe3O4 hybrid deposited on graphene oxide (GO-Fe3O4) on the relative viability and DNA integrity. The properties of the GO-Fe3O4 hybrid were analyzed using a transmission electron microscopy (TEM), X-ray diffraction technique (XRD) and thermal gravimetric method (TGA), while the efficiency of graphene oxide covalent functionalization with iron oxide nanospheres was determined by Fourier transform infrared spectroscopy (FT-IR). L929 and MCF-7 cell lines were selected to analyze the biocompatibility of GO-Fe3O4 nanoparticles. The hybrid was tested using WST-1 and LDH leakage assays. DNA integrity was analyzed by agarose gel electrophoresis and micronucleus assay was performed to examine chromosomal damage in the exposed cell lines. The tested GO-Fe3O4 hybrid did not significantly reduce cell metabolism of L929 cells. GO-Fe3O4 hybrid particles only slightly affected the integrity of cell membranes. DNA integrity and micronucleus assays did not indicate genotoxicity of the hybrid.
Meral Yildirim, Azmi Seyhun Kipcak and Emek Moroydor Derun
In this study, sonochemical-assisted magnesium borate synthesis is studied from different boron sources. Various reaction parameters are successfully applied by a simple and green method. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopies are used to characterize the synthesized magnesium borates on the other hand surface morphologies are investigated by using scanning electron microscope (SEM). The XRD analyses showed that the products were admontite [MgO(B2O3)3 · 7(H2O)] with JCPDS (Joint Committee on Powder Diffraction Standards) no. of 01-076-0540 and mcallisterite [Mg2(B6O7(OH)6)2 · 9(H2O)] with JCPDS no. of 01-070-1902. The results that found in the spectroscopic studies were in a good agreement with characteristic magnesium borate bands in both regions of infra-red and visible. According to SEM results, obtained borates were in micro and sub-micro scales. By the use of ultrasonication, reaction yields were found between 84.2 and 97.9%. As a result, it is concluded that the sonochemical approach is a practicable synthesis method to get high efficiency and high crystallinity in the synthesis magnesium borate compounds.
The surface modified Strychnos potatorum seeds (SMSP), an agricultural waste has been developed into an effective adsorbent for the removal of Zn(II) ions from aqueous environment. The Freundlich model provided a better fit with the experimental data than the Langmuir model as revealed by a high coefficient of determination values and low error values. The kinetics data fitted well into the pseudo-second order model with the coefficient of determination values greater than 0.99. The influence of particle diffusion and film diffusion in the adsorption process was tested by fitting the experimental data with intraparticle diffusion, Boyd kinetic and Shrinking core models. Desorption experiments were conducted to explore the feasibility of regenerating the spent adsorbent and the adsorbed Zn(II) ions from spent SMSP was desorbed using 0.3 M HCl with the efficiency of 93.58%. The results of the present study indicates that the SMSP can be successfully employed for the removal of Zn(II) ions from aqueous environment.
Czesława Rosik-Dulewska, Teresa Krzyśko-Łupicka, Tomasz Ciesielczuk and Łukasz Kręcidło
The soil contaminated with petroleum products must be excluded from the crops and treated to reclamation processes. Natural processes of decomposition of hydrocarbon compounds go very slow, so it is necessary to use bioaugumentation or stimulation in order to accelerate the return of the soil to high culture. In this study the effect of hydrogen peroxide on the process of cleaning soil strongly contaminated with pertochemicals was investigated. For this purpose, a pot experiment lasting 60 days was carried. The dynamics of changes in the population of filamentous fungi, yeasts and bacteria were examined and also content of aliphatic hydrocarbons (n-alkanes), monoaromatic and polycyclic aromatic hydrocarbons (PAHs). Experimental use of hydrogen peroxide in the process of biodegradation of petroleum compounds assisted in the analyzed soil led to an increase of the number of grampositive bacteria during the test. Stimulation of oil products biodegradation by hydrogen peroxide also increased by 35% decomposition efficiency of aliphatic hydrocarbons (C8-C40) and about 50% PAH’s in comparison to control samples without hydrogen peroxide. There was no influence of hydrogen peroxide on the content of monoaromatic hydrocarbons (BTEX) with respect to controls, although in the end of experiment, the total concentration decreased by about 50% compared to the initial content.
Witold Żukowski, Sylwia Englot, Jerzy Baron, Stanisław Kandefer and Małgorzata Olek
Reduction of carbon dioxide emission through the sorption in situ using a fluidised bed reactor
The paper discusses the possibility of using the reversible reaction CaCO3 ↔ CaO + CO2 for the cyclic capture and release of CO2 directly inside a fluidised bed combustor. This could lead to the lowering of CO2 emissions into the atmosphere, as part of an effort to mitigate the greenhouse effect associated with the rising atmospheric CO2 concentrations resulting from obtaining energy from burning fossil fuels.
An enrichment coefficient E has been introduced and defined as a measure of the production of CO2 (on calcining CaCO3) or its removal (on carbonation of CaO) with respect to the level associated with fuel combustion alone. The observations made on the effect of introducing an additional external stream of CO2 on the efficiency of the chemical capture process have been described. Through an appropriate control of the temperature inside the reactor it is possible to change the value of E over the range [-0.8; 0.8]. This implies that up to about 80% of the CO2 derived from the fuel can be temporarily retained within the bed and released later, at a higher concentration. The proposed method of burning fuel in a chemically active fluidised bed could be an available method leading to CO2 isolation from the flue gases and leading to its eventual sequestration.
Gabriela Berkowicz, Witold Żukowski and Jerzy Baron
The paper presents the results of the synthesis of 2,6-dimetyhlphenol (26DMP) from o-cresol. The target compound is an important substrate for polymer chemistry. Due to a large amount of o-cresol which is generated as a by-product, during the synthesis of 2,6-dimethylphenol from phenol, the methylation of o-cresol to 2,6-dimethylphenol should be examined as a separate process. The alkylation of o-cresol was carried out in a fluidized bed of commercial iron-chromium catalyst TZC-3/1. Undesirable decomposition of methyl alcohol on the catalyst generates a number of environmentally dangerous by-products such as methane, carbon dioxide, carbon monoxide. The effect of temperature on the yield of the synthesis was investigated. The synthesis process was monitored on-line in the temperature range 310-380°C, completely covering the maximum efficiency of the process. Online analysis of the process by FTIR spectroscopy gave information about products of both methylation of o-cresol and pyrolysis of methanol. The maximum 85% yield of desired 2,6-dimethylphenol with more than 85% conversion of o-cresol was achieved at 340°C, at 1:6 molar ratio of o-cresol:methanol