Different catalysts for nonoxidative conversion of methane to ethylene and ethane were prepared and evaluated. Both of the products are in high demand,and it is desirable to have a catalyst that is able to convert methane directly to ethane and ethylene. This approach would be especially useful on remote natural gas fields. Monometallic and bimetallic Mo and Fe catalysts were prepared on HZSM-5 support with SiO2/Al2O3 ratio 30. In contrast to already published works,15-23 where similar catalysts were prepared and evaluated for MDA reaction, our aim was to achieve production of ethylene and ethane over a longer period of TOS. We also report the promotional effect of Fe addition to Mo on methane conversion and a relatively stable Fe catalyst for nonoxidative conversion of methane to C2 products.
COBISS.SI-ID: 6687002
This study presents a methodology for analysing Pareto process solutions considering variations in environmental tax rates. Three new combined economic-environmental indicators are defined that measure the relationship between loss of economic value when deviating from the economic optimum, and savings originating from environmental impact reduction at a given environmental tax rate. It is shown that investing in processes or technologies for the reduction of environmental footprints can reduce emissions without worsening economic performance, provided that investors renounce the savings arising from reduced emissions. A multi-period synthesis of a process flow sheet is performed by targeting the economic performance at a given tax rate to the optimal level without any environmental tax.
COBISS.SI-ID: 22629142
Safety is paramount aspect of any chemical plant. In this paper various approaches to enhance process safety are evaluated. The specific enhancements include process design methodologies for improving inherent safety and cognitive engineering to reduce human errors. Their aim is to reduce the number and the consequences of possible deviation events, which depends predominantly on quality of the equipment and human error potential. The consequences are linked to the substances and their inventories. An inherent safety index is used to assess the properties of substances and process units while the potential for human error is characterized using various physiological measures. Our research indicates that application of process synthesis methodologies for simultaneous inherent safety assessment and advanced cognitive engineering approaches for human error reduction will lead to enhanced process safety.
COBISS.SI-ID: 22374934