scholarly journals Impact of Primary and Secondary ZDDP and Ionic Liquid as Lubricant Oil Additives on the Performance and Physicochemical Properties of Pd-Based Three-Way Catalysts

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 878
Author(s):  
Daekun Kim ◽  
Todd J. Toops ◽  
Ke Nguyen ◽  
Michael J. Lance ◽  
Jun Qu
Keyword(s):  
Ionic Liquid ◽  
Inductively Coupled Plasma ◽  
Flow Reactor ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Oxygen Storage Capacity ◽  
Lubricant Additives ◽  
Oxygen Storage ◽  
Base Case ◽  
Shift Reaction

In the present study, two industry primary and secondary zinc dialkyldithiophosphate standards, ZDDP1 and ZDDP2, respectively, are evaluated for their impact on the performance of Pd-based three-way catalyst and bench-marked against two mixed lubricant additives formed from either ZDDP1 or ZDDP2 with a second-generation oil-miscible phosphoric-containing ionic liquid (IL). The three-way catalysts (TWCs) are exposed to the lubricant additives in an engine bench under four different scenarios: a base case with no additive (NA), ZDDP1, IL+ZDDP1, ZDDP2, and IL+ZDDP2. The engine-aged TWC samples are characterized through a variety of analytical techniques, including evaluation of catalyst reactivity in a bench-flow reactor. With respect to the water–gas shift reaction and the oxygen storage capacity, the ZDDP2- and IL+ZDDP2-aged TWC samples are more degraded than the ZDDP1- and IL+ZDDP1-aged TWC samples. X-ray diffraction (XRD) patterns indicate that phosphorus in the form of CePO4 was found to be present in the washcoat of all TWC samples, with the highest amount found in the ZDDP2-aged TWC sample. The results obtained from XRD are further confirmed by those from inductively coupled plasma-optical emission spectroscopy (ICP-OES), which show that more phosphorus is detected in the washcoat of ZDDP2- and IL+ZDDP2-aged TWC samples than in the ZDDP1- and IL+ZDDP1-aged TWC samples.

scholarly journals Migration of Silver and Copper Nanoparticles from Food Coating

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 380
Author(s):  
Hamed Ahari ◽  
Leila Khoshboui Lahijani
Keyword(s):  
Copper Nanoparticles ◽  
Inductively Coupled Plasma ◽  
Food Packaging ◽  
Human Life ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Atomic Emission ◽  
The Body ◽  
Toxic Effects ◽  
Inductively Coupled

Packaging containing nanoparticles (NPs) can increase the shelf life of products, but the presence of NPs may hazards human life. In this regard, there are reports regarding the side effect and cytotoxicity of nanoparticles. The main aim of this research was to study the migration of silver and copper nanoparticles from the packaging to the food matrix as well as the assessment techniques. The diffusion and migration of nanoparticles can be analyzed by analytical techniques including atomic absorption, inductively coupled plasma mass spectrometry, inductively coupled plasma atomic emission, and inductively coupled plasma optical emission spectroscopy, as well as X-ray diffraction, spectroscopy, migration, and titration. Inductively coupled plasma-based techniques demonstrated the best results. Reports indicated that studies on the migration of Ag/Cu nanoparticles do not agree with each other, but almost all studies agree that the migration of these nanoparticles is higher in acidic environments. There are widespread ambiguities about the mechanism of nanoparticle toxicity, so understanding these nanoparticles and their toxic effects are essential. Nanomaterials that enter the body in a variety of ways can be distributed throughout the body and damage human cells by altering mitochondrial function, producing reactive oxygen, and increasing membrane permeability, leading to toxic effects and chronic disease. Therefore, more research needs to be done on the development of food packaging coatings with consideration given to the main parameters affecting nanoparticles migration.

scholarly journals The Effect of Mg and Zn Dopants on Pt/Al2O3 for the Dehydrogenation of Perhydrodibenzyltoluene

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 490
Author(s):  
Rudaviro Garidzirai ◽  
Phillimon Modisha ◽  
Innocent Shuro ◽  
Jacobus Visagie ◽  
Pieter van Helden ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Flow Reactor ◽  
Plug Flow ◽  
Optical Emission ◽  
Catalytic Performance ◽  
Emission Spectrometry ◽  
Hydrogen Yield ◽  
X Ray ◽  
Temperature Programmed

The effects of Mg and Zn dopants on the catalytic performance of Pt/Al2O3 catalyst were investigated for dehydrogenation of perhydrodibenzyltoluene (H18-DBT) as a liquid organic hydrogen carrier. Al2O3 supports were modified with Mg and Zn to produce Mg-Al2O3 and Zn-Al2O3 with a target loading of 3.8 wt.% for dopants. The modified supports were impregnated with chloroplatinic acid solution to produce the catalysts Pt/Al2O3, Pt/Mg-Al2O3 and Pt/Zn-Al2O3 of 0.5 wt.% Pt loading. Thereafter, the catalysts were characterised using inductively coupled plasma- optical emission spectrometry, scanning electron microscopy-energy dispersive X-ray spectroscopy, hydrogen temperature-programmed reduction, carbon-monoxide pulse chemisorption, ammonia temperature-programmed desorption, X-ray diffraction and transmission electron microscopy. The dehydrogenation experiments were performed using a horizontal plug flow reactor system and the catalyst time-on-stream was 22 h. Pt/Mg-Al2O3 showed the highest average hydrogen flowrate of 29 nL/h, while an average of 27 nL/h was obtained for both Pt/Al2O3 and Pt/Zn-Al2O3. This has resulted in a hydrogen yield of 80% for Pt/Mg-Al2O3, 71% for Pt/Zn-Al2O3 and 73% for Pt/Al2O3. In addition, the conversion of H18-DBT ranges from 99% to 92%, Pt 97–90% and 96–90% for Pt/Mg-Al2O3, Pt/Zn-Al2O3 and Pt/Al2O3, respectively. Following the latter catalyst order, the selectivity to dibenzyltoluene (H0-DBT) ranges from 78% to 57%, 75–51% and 71–45%. Therefore, Pt/Mg-Al2O3 showed improved catalytic performance towards dehydrogenation of H18-DBT.

Autothermal Reforming of Propane Over Ni Catalysts Supported on a Variety of Perovskites

2007 ◽  
Vol 7 (11) ◽  
pp. 4013-4016 ◽  
Author(s):  
SeungSoo Lim ◽  
DongJu Moon ◽  
JongHo Kim ◽  
YoungChul Kim ◽  
NamCook Park ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Storage Capacity ◽  
Flow Reactor ◽  
Oxygen Storage Capacity ◽  
Autothermal Reforming ◽  
Oxygen Storage ◽  
Hydrogen Yield ◽  
Impregnation Method ◽  
Ni Catalysts ◽  
Atmospheric Flow

Autothermal reforming of propane for hydrogen over Ni catalysts supported on a variety of perovskites was performed in an atmospheric flow reactor. Perovskite is known for its higher thermal stability and oxygen storage capacity, but catalytic activity of itself is low. A sites of the ABO3 structured perovskites were occupied by La while B sites by one of Fe, Co, Ni, and Al by citrate method. The composition of the reactant mixture was H2O/C/O2 = 8.96/1.0/1.1. The changes in the states of the catalysts after reaction were analyzed by XRD, TPD, and TGA. Ni/LaAlO3 catalyst maintained the perovskite structure after reaction. It showed higher hydrogen yield and thermal stability compared to those of the catalysts with Fe, Co, or Ni in B sites. Catalysts prepared by deposition-precipitation (DP) method showed higher activity than those prepared by impregnation method, presumably due to the smaller sizes of the NiO crystal particles.

scholarly journals Highly Selective Syngas/H2 Production via Partial Oxidation of CH4 Using (Ni, Co and Ni–Co)/ZrO2–Al2O3 Catalysts: Influence of Calcination Temperature

Processes ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 141 ◽  
Author(s):  
Anis Hamza Fakeeha ◽  
Yasir Arafat ◽  
Ahmed Aidid Ibrahim ◽  
Hamid Shaikh ◽  
Hanan Atia ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Partial Oxidation ◽  
Sol Gel ◽  
Analytical Techniques ◽  
Oxygen Storage Capacity ◽  
H2 Production ◽  
Oxygen Storage ◽  
Calcination Temperatures ◽  
Metal Support Interaction

In this study, Ni, Co and Ni–Co catalysts supported on binary oxide ZrO2–Al2O3 were synthesized by sol-gel method and characterized by means of various analytical techniques such as XRD, BET, TPR, TPD, TGA, SEM, and TEM. This catalytic system was then tested for syngas respective H2 production via partial oxidation of methane at 700 °C and 800 °C. The influence of calcination temperatures was studied and their impact on catalytic activity and stability was evaluated. It was observed that increasing the calcination temperature from 550 °C to 800 °C and addition of ZrO2 to Al2O3 enhances Ni metal-support interaction. This increases the catalytic activity and sintering resistance. Furthermore, ZrO2 provides higher oxygen storage capacity and stronger Lewis basicity which contributed to coke suppression, eventually leading to a more stable catalyst. It was also observed that, contrary to bimetallic catalysts, monometallic catalysts exhibit higher activity with higher calcination temperature. At the same time, Co and Ni–Co-based catalysts exhibit higher activity than Ni-based catalysts which was not expected. The Co-based catalyst calcined at 800 °C demonstrated excellent stability over 24 h on stream. In general, all catalysts demonstrated high CH4 conversion and exceptionally high selectivity to H2 (~98%) at 700 °C.

scholarly journals Characterization of Double Leached Waelz Oxide for Identification of Fluoride Mineral

Metals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 361 ◽  
Author(s):  
Suchandra Sar ◽  
Lena Sundqvist Ökvist ◽  
Tobias Sparrman ◽  
Fredrik Engström ◽  
Caisa Samuelsson
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Inductively Coupled Plasma ◽  
Raw Materials ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Sem Analysis ◽  
Waelz Oxide ◽  
Production Knowledge ◽  
Nuclear Magnetic

Double leached Waelz oxide (DLWO), with 76% zinc, is a secondary zinc containing raw materials obtained by the treatment of electric arc furnace dust. The content of fluoride in DLWO is still too high for direct leaching, as fluoride has a detrimental effect on electrowinning for zinc production. Knowledge of the characteristics of DLWO, and especially on how a fluoride mineral might exist, can contribute to further improvement of the selective leaching for the removal of fluoride. In this study, DLWO was characterized using analytical techniques, such as inductively coupled plasma-optical emission spectroscopy (ICP-OES), 19F liquid-state nuclear magnetic resonance (19F LS NMR), X-ray powder diffraction analysis (XRD), scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) and 19F solid-state nuclear magnetic resonance (19F SS NMR). This study showed that DLWO mainly consisted of zincite (ZnO), cerussite (PbCO3) and a spinel containing zinc, iron and manganese. The fluoride mineral identified was calcium fluoride (CaF2). In SEM analysis, fluorine was found in larger grains together with calcium and oxygen, which was possibly calcium carbonate.

scholarly journals Spectroscopic, Textural and Thermal Characterization Methods of Biostimulants Based on Sodium Humate

2019 ◽  
Vol 69 (12) ◽  
pp. 3477-3482
Author(s):  
Rusandica Stoica ◽  
Florin Oancea ◽  
Iulian Minca ◽  
Sanda Maria Doncea ◽  
Rodica Ganea ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Raw Materials ◽  
Nutrient Use Efficiency ◽  
Reference Method ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
Essential Information ◽  
Complex Investigation ◽  
Characterization Methods

Plant biostimulants, an emerging class of agricultural inputs, are complex products. The reproducibility of their specific action on plant metabolism and plant physiology, which lead to an enhanced nutrient use efficiency, stress tolerance and edible yield quality, is still a challenge. Development of quality insurance systems for plant biostimulants need complex investigation based on adapted analytical, physico-chemical and chemical methods. The objective of this work was to characterize commercial humate biostimulants through different analytical techniques (Fourier transform infrared spectroscopy - FTIR, thermogravimetric analysis- TGA) and to evaluate their textural and chemical (pH, C, N, humic acids, inorganic components) parameters. The first derivative curve from TG analysis showed decomposition of different compounds, classified according to the results obtained by FTIR. The humic substances determined by TGA method was comparable with the results obtained by gravimetric reference method. The inductively coupled plasma-optical emission spectrometry (ICP-OES) technique was applied to determine the inorganic elements either from the production process of humate or from raw materials, as well as for the control of humate in terms of requirements for safety and quality. Their complementary properties obtaining through different analytical techniques provide essential information on the chemical characteristics of the humate plant biostimulant formulations.

scholarly journals Thermal and Calorimetric Evaluations of Some Chemically Modified Carbohydrate-Based Substrates with Phosphorus-Containing Groups

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 588 ◽  
Author(s):  
Ananya Thomas ◽  
Paul Joseph ◽  
Khalid Moinuddin ◽  
Haijin Zhu ◽  
Svetlana Tretsiakova-McNally
Keyword(s):  
Solid State ◽  
Inductively Coupled Plasma ◽  
31P Nmr ◽  
Potato Starch ◽  
Analytical Techniques ◽  
Optical Emission ◽  
31P Nmr Spectroscopy ◽  
Icp Oes ◽  
Thermal Stabilities ◽  
Inductively Coupled

In the present article, we report on the chemical modifications of some carbohydrate-based substrates, such as potato starch, dextran, β-cyclodextrin, agar agar and tamarind, by reacting with diethylchlorophosphate (DECP), in dispersions in dichloromethane (DCM), in the presence of triethylamine (TEA) as the base. The modified substrates, after recovery and purification, were analyzed for their chemical constitutions, thermal stabilities and calorimetric properties using a variety of analytical techniques. These included: solid-state 31P NMR, inductively coupled plasma-optical emission spectroscopy (ICP-OES), thermogravimetric analysis (TGA) and pyrolysis combustion flow calorimetry (PCFC). The unmodified counterparts were also subjected to the same set of analyses with a view to serving as controls. Phosphorus analyses, primarily through ICP-OES on the recovered samples, showed different degrees of incorporation. Such observations were optionally verified through solid-state 31P NMR spectroscopy. The thermograms of the modified substrates were noticeably different from the unmodified counterparts, both in terms of the general profiles and the amounts of char residues produced. Such observations correlated well with the relevant parameters obtained through PCFC runs. Overall, the modified systems containing phosphorus were found to be less combustible than the parent substrates, and thus can be considered as promising matrices for environmentally benign fire-resistant coatings.

scholarly journals Kinetics of conversion of celestite to strontium carbonate in solutions containing carbonate, bicarbonate and ammonium ions and dissolved ammonia

2014 ◽  
Vol 79 (3) ◽  
pp. 345-359 ◽  
Author(s):  
Mert Zoraga ◽  
Cem Kahruman
Keyword(s):  
Particle Size ◽  
Inductively Coupled Plasma ◽  
Reaction Rate ◽  
Analytical Techniques ◽  
Optical Emission ◽  
Ion Concentration ◽  
Emission Spectrometry ◽  
Conversion Reaction ◽  
Inductively Coupled ◽  
Shrinking Core

Celestite concentrate (SrSO4) has been converted to SrCO3 in solutions containing CO32-, HCO3- and NH4+ ions and dissolved ammonia. The effects of stirring speed, CO32- ion concentration; temperature and particle size of SrSO4 on the reaction rate were investigated. It was found that the conversion of SrSO4 was increased by increasing the temperature and decreasing the particle size, while the reaction rate was decreased with increasing the CO32- ion concentration. However, there was no effect of the stirring speed on the reaction rate. The conversion reaction was under chemical reaction control and the Shrinking Core Model was suitable to explain the reaction kinetics. The activation energy for the conversion reaction was found to be 41.9 kJ mol-1. The amounts of the elements in the reaction solution were determined quantitatively by inductively coupled plasma-optical emission spectrometry. The characterization of the solid reactant and product was made using scanning electron microscopy-energy dispersive spectrometry and X-ray powder diffraction analytical techniques.

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