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Major Advances and Challenges in Heterogeneous Catalysis for Environmental Applications: A Review

Abstract

Heterogeneous catalysis is one of the fastest developing branches of chemistry. Moreover, it is strongly connected to popular environment-related applications. Owing to the very fast changes in this field, for example, numerous discoveries in nanoscience and nanotechnologies, it is believed that an update of the literature on heterogeneous catalysis could be beneficial. This review not only covers the new developments of heterogeneous catalysis in environmental sciences but also touches its historical aspects. A short introduction to the mechanism of heterogeneous catalysis with a small section on advances in this field has also been elaborated. In the first part, recent innovations in the field of catalytic air, water, wastewater and soil treatment are presented, whereas in the second part, innovations in the use of heterogeneous catalysis for obtaining sustainable energy and chemicals are discussed. Catalytic processes are ubiquitous in all branches of chemistry and there are still many unsolved issues concerning them.

Open access
New Methods of Natural Gas Adjusting for Technological Purposes Based on Modern Filtration Materials

Abstract

Reservoir gas treatment technologies currently in use require significant investments in equipment and materials. Considering the foregoing, new technologies are sought for treatment and separation of components of extracted gas. They will guarantee compliance with gas quality requirements arising from applicable standards while at the same time lowering the costs of investment, service and environmental protection. Therefore, the purpose of this work was to develop an efficient mobile technology for natural gas treatment, on the basis of advanced filtering and coalescing materials and membranes, which eliminate the existing, economically non-viable processes and reduce the costs related to development of new reservoirs. The purpose of designed materials was removal of solid particles, water, higher hydrocarbons and nitrogen from natural gas. Presented integrated filtration and membrane system, characterized by a highly compact design enabling installation in container stations and transporting the system between specific points of production.

Open access
Online Measurement Method of Water Quality in the Sulejow Reservoir

Abstract

The paper presents methodology of accurate mobile measurements of water quality parameters such as temperature, dissolved oxygen, chlorophyll “a” concentration, ammonium ion concentration, conductivity, pH and blue-green algae content in water. The measurements (probe EXO 2, YSI, USA) were made on various depths of probe immersion (1.5, 2.5 and 3.5 m) and at different towing speeds of the probe (approx. 5.4 and 9.0 km/h). Static measurements carried out on the same route provided reference values for the measurements in motion to compare the repeatability of static and mobile methods. The tests were also evaluated by observation of probe behavior in motion, e.g. water disturbance intensity, access of light (sun rays) to the sensors. Statistical tests confirmed that the mean values of water quality parameters from mobile measurements with the speed of 5.4 km/h at the depth 1.5 m does not differ from the stationary measurements. Results of statistical analysis prove that water quality parameters can be measured accurately keeping established speed of towing the probe at the fixed depth. Methodology of mobile measurements elaborated in the frame of this work allows to collect vast number of data which can be used to obtain GIS point maps of water quality parameters in large water bodies.

Open access
Quality of Rivers: Comparison of Hydro-Morphological, Physical-Chemical and Biological Methods

Abstract

The study was performed in five fourth-order tributaries of the Bystrzyca Lubelska River (Eastern Poland, Lublin Upland), differing in the degree of river-bed transformation and level of pollution. Hydro-morphological methods (descriptive method by Ilnicki and Lewandowski - IL, and index method by Oglecki and Pawlat - OP) and biological indices based on the composition of zoobenthos (Diversity - D, and index based on proportions between the density of Oligochaeta and Chironomidae - O/Ch) permitted distinguishing of four classes, from II to V. The distinguishing of only two quality classes (III and IV) was possible by means of physical-chemical methods and by benthic index BMWP_PL. Those two methods seem to show the lowest sensitivity to the spatial variability of the environment quality. The BMWP_PL index was the least sensitive to year-to-year environmental changes, and O/Ch was the most sensitive. Relatively high conformity was obtained between hydro-morphological assessments performed by means of the OP and IL methods. Results obtained by means of these tools weakly corresponded with the physical-chemical assessments. The latter assessments were the most similar to those obtained by means of the BMWP_PL (degree of similarity = 57%) and D (47%) indices, and considerably less in the case of O/Ch (36%). The BMWP_PL and D indices better corresponded with the results of the hydro-morphological assessment performed by means of the IL method than with those performed by means of the OP method while D index showed a reverse pattern. The O/CH index proved useful for the assessment of the degree of organic pollution of the river’s water, but not the sediments.

Open access
Reservoir’s Impact on the Water Chemistry of the Teesta River Mountain Course (Darjeeling Himalaya)

Abstract

The article presents the role of the newly built reservoir in the formation of the hydrochemistry of water of the Teesta River (a tributary of the Brahmaputra) in its Himalayan course. Field research were performed in the post-monsoon season of the period 2013-2015. Sampling and measuring points were located in five points over 43 km of the Teesta River in the Darjeeling Himalaya. Analysis of water along of river longitudinal profile above and below the reservoir suggest that the reservoir caused decrease most of the basic ions concentrations (Cl, K+, Na+, Mg2+, NO3 and PO4 3−). An inverse trend was observed only with respect to Ca2+, SO4 2− and NH4 +. The dam does not influent on the F concentration. The reservoir causes minor enrichment most of the heavy metals such Cu, Ni, Zn, Cr, Cd and Sr. The lower enrichment of Teesta water below the dam indicates the water self-purification processes for metals by the Teesta Reservoir. The changes of physicochemical properties and concentrations of ions caused by the reservoir are usually normalised by environmental factors before the Teesta River outlet from the Himalayas (within 15 km of the river).

Open access
The Role of Mineral Phases in the Biogas Production Technology

Abstract

In the field of electric power industry, renewable energy sources, fertilisers, reclamation, and waste management, biomass is widely studied and used. Minerals are present in every step of biogas transformation, but their forms, occurrence, and composition have not been studied yet. However, there is no comprehensive study research that would address the presence of mineral phases in the process of biogas production. This aim of the study is determination of the amount and composition of the mineral phases present in fermentation residues resulting from different production technologies. Digestate mineral composition was analysed using 46 samples from agricultural biogas plants and university testing biogas reactor. The majority of samples contained the amorphous phase. Minority phases consisted of quartz, albite, orthoclase, muscovite, and amphibole. Opal-CT was found in eleven samples (1.26 to 12.1% wt.). The elements present in gas-liquid fluids or in liquids, gases and aerosols within the biogas technology system may create mineral phases, namely the amorphous phase or the crystalline phase under certain conditions. Opal-CT may enter the fermenter as part of plant tissues referred to as phytoliths, or as an unwanted admixture of different origin. It may also originate from the present amorphous SiO2.

Open access
The Effect of Ionic Liquids With (–)-Menthol Derivative Containing a Chloride Anion to Weed

Abstract

Weeds constitute a huge group of undesirable plants, widespread throughout the world. They represent a big problem for most farmers, who implement different methods to fight against them. Thanks to their wide occurrence, weeds however, can be an excellent indicator of the quality of soil and the whole environment where they are present. In this paper, we present the impact of four alkylimidazolium chlorides with a natural terpene component introduced into the soil: (1R,2S,5R)-(–)-menthol and alkyl substituents containing 1, 4, 9 or 12 carbon atoms, on the growth and development of selected weed species. Compounds with the highest phytotoxic activity towards gallant soldier, white goosefoot and common sorrel were chlorides with methyl and butyl substituents, while compounds with nonyl and dodecyl substituents demonstrated a weak effect on these weeds. Phytotoxicity of the salts tested was largely dependent on the applied concentration of the compound and the genetic make-up of plant species used in the experiment. This was reflected in the inhibition of plants’ length and their roots, as well as changes in the content of dry matter and photosynthetic pigments.

Open access
The Effect of Landscape on the Diversity in Urban Green Areas

Abstract

This article presented the results of a comparative analysis of carabid species compositions (Coleoptera: Carabidae) in urban green areas of the City of Lublin, Eastern Poland. In this study, the occurrence and abundance of ground beetles were analysed according to habitat preference and dispersal ability. A total of 65 carabid species were found in the three green areas. Obviously, the high species richness of ground beetles in the greenery of the Lublin is determined by the mostly undeveloped floodplain of the river Bystrzyca. The species richness of carabids and their relative abundance decrease in the assemblage of green areas under the effect of isolation of green patches and fragmentation of the semi-natural landscape elements in the urban environment. Generalists and open-habitat species significantly prevailed in all green areas. The prevailing of riparian and forest species at floodplain sites of the river Bystrzyca demonstrated the existence of a connection of the carabid assemblage with landscape of river valley. The Saski Park and gully “Rury” are more influenced by urbanization (fragmentation, isolation of green patches) and recreation that is consistent with the significant prevalence of open-habitats species in the carabid beetle assemblage.

Open access
Estimating Root Zone Moisture from Surface Soil Using Limited Data

Abstract

For estimation of root-zone moisture content from EO-1/Hyperion imagery, surface soil moisture was first predicted by hyperspectral reflectance data using partial least square regression (PLSR) analysis. The textures of more than 300 soil samples extracted from a 900 m × 900 m field site located within the Hetao Irrigation District in China were used to parameterize the HYDRUS-1D numerical model. The study area was spatially discretized into 18,000 compartments (30 m × 30 m × 0.02 m), and Monte Carlo simulations were applied to generate 2000 different soil-particle size distributions for each compartment. Soil hydraulic properties for each realization were determined by application of artificial neural network analysis and used to parameterize HYDRUS-1D to simulate averaged soil-moisture contents within the root zone (0-40 cm) and surface (approximately 0-4 cm). Then the link between surface moisture and root zone was established by use of linear regression analysis, resulting in R and RMSE of 0.38 and 0.03, respectively. Kriging and co-kriging with observed surface moisture, and co-kriging with surface moisture obtained from Hyperion imagery were also used to estimate root-zone moisture. Results indicated that PLSR is a powerful tool for soil moisture estimation from hyperspectral data. Furthermore, co-kriging with observed surface moisture had the highest R (0.41) and linear regression model, and HYDRUS Monte Carlo simulations had a lowest RMSE (0.03) among the four methods. In regions that have similar climatic and soil conditions to our study area, a linear regression model with HYDRUS Monte Carlo simulations is a practical method for root-zone moisture estimation before sowing and it can be easily coupled with remote sensing technology.

Open access
The Honey as a Bioindicator of the Environment

Abstract

Monofloral rape, sunflower, linden and acacia honeys as well as honeys sampled within and around the Austrian towns Vienna and Linz, as well as in rural areas in Lower Austria, were analysed for main and trace elements. The results were tested to be used as indication of urban dust exposure. Main elements of the ash are K, P, and B, which are specific for plant origin. Ash based data correct for dilutions by the sugar matrix. They showed enrichments of Cu, Zn and Mo, whereas the contaminant elements Cd, Pb and Co were found at about the same levels as expectable in dust. Ash-based Al, Fe, Cr and Li were much lower than soil levels obtainable from aqua regia. Among the monofloral honey samples, the effect of adjacent soil was largest for Mn. Most differences between rural areas and urban areas in Vienna and Linz were within experimental errors, both per sample weight and per ash weight. In cases honey samples are considered to trace contaminations, the additional use of ash-based data is recommended.

Open access