ZrxMg1-xO supported cobalt catalysts for methane decomposition into COx-free hydrogen and carbon nanotubes

Zirconia-magnesia supported cobalt catalysts with various Zr/Mg atomic ratios were prepared and evaluated for non-oxidative catalytic decomposition of methane to produce CO_x-free hydrogen and carbon nanotube. The catalytic performance of the catalysts was performed in a continuous fixed bed flow reactor at 700°C under atmospheric pressure. The fresh and spent catalysts were characterized by XRD, TPR, BET, TEM, and Raman spectroscopy. The results showed that the change in Zr/Mg ratio of the mixed oxide support has a significant effect on the catalytic performance of the active Co metal. The catalyst 30%Co/Zr_0.8Mg_0.2 showed the highest activity and stability within the used series of catalysts with hydrogen yield reached up to 79%. Both Co/Mg_1.0 and Co/Zr_1.0 showed poor stability due to strong Co-Mg interaction and aggregation of Co species on Zr support, respectively. All catalysts produced mainly MWCNTs with different diameters depending on the Zr/Mg ratio. The outer diameter increased with increasing Zr content in the catalyst due to the enlargement of the particle size of cobalt as a result of aggregation.     

Comparison of floating-bed wetland and gravel filter amended with limestone and sawdust for sewage treatment

Environmental Science and Pollution Research - Advancements in the design and technology of constructed wetlands for efficient removal of wastewater contaminants are ever in progress to develop...     

Biosurfactant electrospun nanofibers exhibit minimal side effects on the structure and function of the liver tissue in male rat model

Environmental Science and Pollution Research - Oil spills can result in significant damage to marine estuaries, rivers, lakes, wetlands, and shorelines. Electrospun nanofibers containing...     

Optimizing contract allocation for risky conservation tenders

In the face of a shrinking budget for environmental activities, conservation agencies must design and implement agri-environmental policies that cost-effectively meet the environmental objectives. However, designing such programs is often challenging due to different uncertainties. For example, landholders may be exposed to risks when carrying out conservation projects. To minimise the negative impact of unexpected losses, landholders may require additional financial incentives as compensation for undertaking “risky” conservation projects. In such situations, the conservation agency risks over-spending public funds because of prohibitively high opportunity costs from landholders or failing to meet the environmental target. We used analytical and simulation approaches to explore optimal budget allocation in a target-constrained conservation tender. We also compared the performance of the tender with and without own-cost uncertainty. Results showed that as landholders’ own-cost uncertainty rises, the conservation agency is forced to allocate more funding to secure the same level of the environmental target. We found that the optimal funding level is sensitive to landholders’ competition uncertainty and the magnitude of expected losses.

     

Estimating Population Size and Detection Probability of the Lorestan Newt,Neurergus kaiseri (Schmidt, 1952) using an Integrated Method

Russian Journal of Ecology - Robust estimates of species population abundance are necessary for the success of conservation plans and species management strategies. In the present study, our main...     

Extracting urban impervious surfaces from Sentinel-2 and Landsat-8 satellite data for urban planning and environmental management

Environmental Science and Pollution Research - Impervious surface is mainly defined as any surface which water cannot infiltrate the soil. Due to the impact of urban impervious surfaces (UIS) on...     

How economics can further the success of ecological restoration

Restoration scientists and practitioners have recently begun to include economic and social aspects in the design and investment decisions for restoration projects. With few exceptions, ecological restoration studies that include economics focus solely on evaluating costs of restoration projects. However, economic principles, tools, and instruments can be applied to a range of other factors that affect project success. We considered the relevance of applying economics to address 4 key challenges of ecological restoration: assessing social and economic benefits, estimating overall costs, project prioritization and selection, and long‐term financing of restoration programs. We found it is uncommon to consider all types of benefits (such as nonmarket values) and costs (such as transaction costs) in restoration programs. Total benefit of a restoration project can be estimated using market prices and various nonmarket valuation techniques. Total cost of a project can be estimated using methods based on property or land‐sale prices, such as hedonic pricing method and organizational surveys. Securing continuous (or long‐term) funding is also vital to accomplishing restoration goals and can be achieved by establishing synergy with existing programs, public–private partnerships, and financing through taxation.     

Vacuum pyrolysis of polymeric wastes containing hazardous cyano groups

Vacuum pyrolysis of polymeric wastes containing hazardous cyano groups was studied using low temperature pyrolysis mass spectrometry. Specifically, the study analyzed the presence of toxic compounds among the pyrolysis products. The polymers were pyrolyzed directly in the solid probe of a quadruple mass spectrometer within an ion source at a pressure of 10^?6 Torr and then sorted by quadrupole mass analyzer. Polyethyl cyanoacrylate degrades by depolymerization, mostly into the ethyl cyanoacrylate monomer units. The degradation of polyurethane produces nonpolymeric urethane, isocyanates, amines and ethers. Polyacrylonitrile degrades via a depolymerization pathway into oligonitriles, acrylonitrile, ammonia and hydrogen cyanide.