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International trade in herbs and spices is showing steady growth. This may contribute to the deterioration of their quality (complex supply chains) and the search for alternative, cheaper sources (adulteration). This paper presents the results of quality control of culinary herbs available on the European markets. Eight spices were evaluated: savory, lovage, basil, thyme, marjoram, oregano, fennel, mustard. The tests were performed (from January 2022 till January 2023) for three production batches from five different suppliers, and analyzed such parameters as aroma, overall appearance, impurity content, net weight, moisture content, ash content and essential oils. The analyzed parameters are the basic quality characteristics controlled by institutions overseeing the quality of foodstuffs. The determinations were made on the basis of European standards. The results show deviations from the standards especially in the content of essential oils. Slight exceedances of the standards were also recorded for water and total ash content. On the other hand, for such parameters as net weight, impurity content, general appearance or odor, no overstepping of acceptable standards was recorded.

A new type of compact, portable fixed-bed reactor integrated with a heat transfer system was developed for the removal of volatile and flammable air pollutants such as lean methane and volatile organic compounds (VOCs). The reactor may operate in catalytic or thermal combustion conditions with the purpose of achieving autothermal processes with the possibility of energy recovery. An excess heat recovery point was designed behind the reactor bed at the place where the gas temperature is the highest to enable its usage. The mathematical model is presented together with a number of simulation calculations performed for the assessment of the developed reactor. The case study in this paper was for catalytic methane oxidation at a temperature of 400 °C, a methane concentration between 0.1% and 2% by weight, a gas flow rate of 1 m3/s STP, and a heat exchange surface for the assumed plate exchanger from 10 to 200 m2. The calculations show that the thickness of the insulation is of little importance for the operation of the equipment, and a sufficient thickness was about 20–50 mm. The optimal area for the considered case is 80–100 m2. It was found that recovery of thermal energy is possible only for higher methane concentrations, above 0.3% by weight. Using an appropriate surface for the exchanger, it is possible to recover even 50% of the combustion enthalpy at a methane concentration of 0.45% by weight. For an exchanger area below 50 m2, the recoverable energy drops rapidly. It was found that the exchanger area is the most important equipment parameter under consideration. [ABSTRACT FROM AUTHOR]

Carbon dioxide desorption from a monoethanolamine (MEA) solution using a hydrophobic polydimethylsiloxane (PDMS) tubular membrane on a ceramic support is presented. The effects of operating parameters such as feed temperature, liquid flow rate and MEA concentration on mass transfer were examined. The mass transfer of CO2 from the liquid to gaseous phase was predicted by a multilayer film model with an accuracy of ±25%. Research into new selective materials is needed to develop more efficient and environmentally friendly CO2 capture technology

This work presents the experimental research on feasible intensification of CO2/N2 separation by utilization of the developed supported ionic liquid membranes (SILMs). SILMs were developed through specific impregnation of commercially available ceramic microfiltration/ultrafiltration membranes made by INOPOR and polydimethylsiloxane (PDMS) membranes made by Pervatech BV with chosen imidazolium based ionic liquids (ILs). The effects of operating parameters, impregnation method, and SILM thickness were analyzed. The impregnation was performed by coating and soaking methods at normal pressure and under vacuum. The proper impregnation of the ceramic support, especially in case of commercial PDMS membranes, allows to achieve two distinct, stable, highly selective separation layers. The comparison of separation efficiency of the investigated SILMs shows that SILM based on PDMS membrane prepared by coating with 1‐ethyl‐3‐methylimidazolium acetate ([Emim][Ac]) has very good stability, high CO2/N2 ideal separation factor of 152 and permeability of 2400 barrer. It was found that optimum operating conditions were feed temperature of 20°C and pressure below 200 kPa. The obtained results represent an interesting low cost alternative in the gas separation, especially when the choice of selectivity is the first priority. The comparison with literature data and upper bond Robeson correlation (2008) suggests, that applying an additional active separating IL layer and an appropriate impregnating method to the commercial ceramic membranes may result in significant improvement of separation efficiency. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The separation of CO2/N2 by supported ionic liquid membranes (SILMs) is presented. SILMs have been developed through impregnation of the ceramic support nanopores of commercial PDMS (polidimethylosiloxane) membranes (made by Pervatech BV) and commercial microfiltration membranes (made by Inopor) with 1-ethyl-3-methylimidazolium acetate ([Emim][Ac]). Comparison of the separation efficiency of SILMs prepared on the same ceramic supports shows that SILMs based on PDMS membranes show good stability and very high CO2/N2 selectivity. The obtained results present an inexpensive alternative in selective CO2/N2 separation by SILMs, especially when the choice of selectivity is the first priority. Comparison with Robeson upper bound correlation and literature data shows that applying the ionic liquid and appropriate impregnation method to PDMS membranes results in a significant improvement in separation performance. [ABSTRACT FROM AUTHOR]

The comparison study of CO2 removal efficiency from flue gases at low pressures and temperatures is presented, based on commonly used methods and materials. Our own experimental results were compared and analyzed for different methods of CO2 removal from flue gases: absorption in a packed column, adsorption in a packed column and membrane separation on polymeric and ceramic membranes, as well as on the developed supported ionic liquid membranes (SILMs). The efficiency and competitiveness comparison of the investigated methods showed that SILMs obtained by coating of the polydimethylsiloxane (PDMS) membrane with 1-ethyl-3-methylimidazolium acetate ([Emim][Ac]) exhibit a high ideal CO2/N2 selectivity of 152, permeability of 2400 barrer and long term stability. Inexpensive and selective SILMs were prepared applying commercial membranes. Under similar experimental conditions, the absorption in aqueous Monoethanolamine (MEA) solutions is much faster than in ionic liquids (ILs), but gas and liquid flow rates in packed column sprayed with IL are limited due to the much higher viscosity and lower diffusion coefficient of IL. For CO2 adsorption on activated carbons impregnated with amine or IL, only a small improvement in the adsorption properties was achieved. The experimental research was compared with the literature data to find a feasible solution based on commercially available methods and materials. [ABSTRACT FROM AUTHOR]