scholarly journals Comparative study on one-step pyrolysis activation of walnut shells to biochar at different heating rates

2021 ◽  
Vol 7 ◽  
pp. 388-396
Author(s):  
Abdulmajid Abdullahi Shagali ◽  
Song Hu ◽  
Yankui Wang ◽  
Hanjian Li ◽  
Yi Wang ◽  
...  
Keyword(s):  
Comparative Study ◽  
Heating Rates ◽  
Walnut Shells ◽  
One Step

Global Reaction Model to Describe the Kinetics of Catalytic Pyrolysis of Coffee Grounds Waste

2017 ◽  
Vol 899 ◽  
pp. 173-178 ◽  
Author(s):  
Ronydes Batista Jr. ◽  
Bruna Sene Alves Araújo ◽  
Pedro Ivo Brandão e Melo Franco ◽  
Beatriz Cristina Silvério ◽  
Sandra Cristina Danta ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Large Scale ◽  
Catalytic Pyrolysis ◽  
Petroleum Products ◽  
Reaction Model ◽  
Heating Rates ◽  
Coffee Grounds ◽  
One Step ◽  
Global Reaction ◽  
The One

In view of the constant search for new sources of renewable energy, the particulate agro-industrial waste reuse emerges as an advantageous alternative. However, despite the advantages of using the biomass as an energy source, there is still strong resistance as the large-scale replacement of petroleum products due to the lack of scientifically proven efficient conversion technologies. In this context, the pyrolysis is presented as one of the most widely used thermal decomposition processes. The knowledge of aspects of chemical kinetics, thermodynamics these will, heat and mass transfer, are so important, since influence the quality of the product. This paper presents a kinetic study of slow pyrolysis of coffee grounds waste from dynamic thermogravimetric experiments (TG), using different powder catalysts. The primary thermal decomposition was described by the one-step reaction model, which considers a single global reaction. The kinetic parameters were estimated using nonlinear regression and the differential evolution method. The coffee ground waste was dried at 105°C for 24 hours. The sample in nature was analyzed at different heating rates, being 10, 15, 20, 30 and 50 K/min. In the catalytic pyrolysis, about 5% (w/w) of catalyst were added to the sample, at a heating rate of 30 K/min. The results show that the one-step model does not accurately represent the data of weight loss (TG) and its derivative (DTG), but can do an estimative of the activation energy reaction, and can show the differences caused by the catalysts. Although no one can say anything about the products formed with the addition of the catalyst, it would be necessary to micro-pyrolysis analysis, we can say the influence of the catalyst in the samples, based on the data obtained in thermogravimetric tests.

A comparative study evaluating the esophageal transit time of eight healthy cats when pilled with the FlavoRx pill glide versus pill delivery treats

2010 ◽  
Vol 12 (4) ◽  
pp. 286-290 ◽  
Author(s):  
Alexander D. Bennett ◽  
Catriona M. MacPhail ◽  
Debra S. Gibbons ◽  
Michael R. Lappin
Keyword(s):  
Comparative Study ◽  
Transit Time ◽  
Esophageal Stricture ◽  
Stricture Formation ◽  
Delivery Method ◽  
Esophageal Transit ◽  
One Step

Retention of tablets or capsules in the feline esophagus can be associated with esophagitis and esophageal stricture formation. The objective of this study was to evaluate the esophageal passage of tablets and capsules when administered with either a one-step pill gun with flavored liquid (FlavoRx pill glide) or a pill delivery treat (Pill Pockets). Four different medication administrations were evaluated on different days in eight normal cats: tablets with FlavoRx pill glide (T-FG), tablets with pill delivery treats (T-PP), capsules with FlavoRx pill glide (C-FG) and capsules with pill delivery treats (C-PP). The estimated average transit time was 36 s for T-FG, 60 s for T-PP, 16 s for C-FG, and 24 s for C-PP. The results of this study suggest that either pill delivery method is acceptable for successful passage of tablets or capsules into the stomach of cats using a single replicate.

Comparative study of conventional vs. one-step-interconnected (OSI) monolithic CdTe modules

2015 ◽  
Vol 19 (7) ◽  
pp. 488-493
Author(s):  
G. Kartopu ◽  
M. Crozier ◽  
A. Brunton ◽  
V. Barrioz ◽  
S. Hodgson ◽  
...  
Keyword(s):  
Comparative Study ◽  
One Step

scholarly journals 4-Nitrophenyl activated esters are superior synthons for indirect radiofluorination of biomolecules

2020 ◽  
Vol 11 (8) ◽  
pp. 919-922
Author(s):  
Mohammad B. Haskali ◽  
Ashleigh L. Farnsworth ◽  
Peter D. Roselt ◽  
Craig A. Hutton
Keyword(s):  
Comparative Study ◽  
Small Molecules ◽  
Activated Esters ◽  
One Step ◽  
Prosthetic Groups

A comparative study of PNP- and TFP-activated esters of radiolabelled prosthetic groups demonstrates the superiority of PNP esters in terms of stability and yields for use in one-step radiolabelling of small molecules and peptides.

Effect of Sintering Conditions on Mechanical and Optical Properties of 3Y-TZP Dental Ceramic

2014 ◽  
Vol 608 ◽  
pp. 181-186
Author(s):  
Kannigar Dateraksa ◽  
Sukunthakan Ngernbamrung ◽  
Ryan C. McCuiston
Keyword(s):  
Fracture Toughness ◽  
Optical Properties ◽  
High Strength ◽  
Dental Ceramics ◽  
Heating Rates ◽  
Microstructural Characteristics ◽  
One Step ◽  
Sintering Conditions ◽  
Dental Applications ◽  
Spray Dried

The use of zirconia dental ceramics has grown in recent years due to improvements in esthetics and biocompatibility. Zirconia is used in dental applications for its high strength and fracture toughness. In this research, the influence of sintering conditions on the strength and optical properties of zirconia was investigated. Spray dried granules of 3Y-TZP zirconia were die pressed into disc-shaped samples and cold isostatic pressed at 250 MPa. Sintering was conducted using either one step sintering at 1500 oC or two-step sintering, with pre-sintering at 1200 oC and final sintering at 1500 oC. Heating rates of 2 and 10 oC/min were used. The biaxial flexural strength, fracture toughness, density, microstructural characteristics and optical properties of the sintered samples were determined. It was found that the sintering conditions did appear to influence the mechanical and optical properties. The sintering conditions had no significant effect on the density. It was concluded that for the sintering conditions examined, the two-step sintering with a heating rate of 2 oC/min produced the best average mechanical and optical properties of 3Y-TZP zirconia.

Kinetic Analysis on Catalytic Co-Gasification of Rubber Seed Shell and High Density Polyethylene Mixtures

2014 ◽  
Vol 625 ◽  
pp. 251-254
Author(s):  
Bridgid Chin Lai Fui ◽  
Suzana Yusup ◽  
Ahmed Al Shoaibi ◽  
Pravin Kannan ◽  
Chandrasekar Srinivasakannan ◽  
...  
Keyword(s):  
High Density Polyethylene ◽  
Weight Ratio ◽  
High Density ◽  
Heating Rates ◽  
Exponential Factor ◽  
Rubber Seed ◽  
Gasification Process ◽  
System A ◽  
One Step ◽  
Decomposition Behavior

In this paper, the catalytic co-gasification of rubber seed shell and high density polyethylene mixtures (0.2:0.8 weight ratio of HDPE:RSS) are investigated using a non-isothermal thermogravimetric analysis (TGA) system in a range of heating rates of 10, 20, 30 and 50 K/min within the temperature range of 323-1173 K. The argon gas is supplied at a flowrate of 100 ml/min and the steam is generated from superheater at 383 K. The steam is injected at flowrate of 300 μL/hour into the TGA system. A commercial nickel powder is used as the catalyst for the gasification process. The thermal decomposition behavior and synergistic effect of the HDPE/RSS mixture are investigated. The activation energy, EA and pre-exponential factor, A are determined based on one step integral method.

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