Abstract

Adsorption heat transformation (AHT) systems can play a major role in protecting our environment by decreasing the usage of fossil fuels and utilizing natural and alternative working fluids. The adsorption isotherm is the most important feature in characterizing an AHT system. There are eight types of International Union of Pure and Applied Chemistry (IUPAC) classified adsorption isotherms for different “adsorbent-adsorbate” pairs with numerous empirical or semi-empirical mathematical models to fit them. Researchers face difficulties in choosing the best isotherm model to describe their experimental findings as there are several models for a single type of adsorption isotherm. This study presents the optimal models for all eight types of isotherms employing several useful statistical approaches such as average error; confidence interval (CI), information criterion (ICs), and proportion tests using bootstrap sampling. Isotherm data of 13 working pairs (which include all eight types of IUPAC isotherms) for AHT applications are extracted from literature and fitted with appropriate models using two error functions. It was found that modified Brunauer–Emmet–Teller (BET) for Type-I(a) and Type-II; Tóth for Type-I(b); GAB for Type-III; Ng et al. model for Type-IV(a) and Type-IV(b); Sun and Chakraborty model for Type-V; and Yahia et al. model for Type-VI are the most appropriate as they ensure less information loss compared to other models. Moreover; the findings are affirmed using selection probability; overall; and pairwise proportion tests. The present findings are important in the rigorous analysis of isotherm data.

Highlights

  • To reduce global electricity demand, scientists are paying considerable attention to adsorption heat transformation (AHT) technologies such as cooling and heating as they can be driven by renewable energy or waste heat having a temperature of as low as 60 ◦ C [1]

  • The main aim of the current study is to find out optimal models for all the eight types of isotherms employing several statistical tools such as average error, confidence interval (CI), information criterion (IC’s), and proportion tests using bootstrap sampling

  • Relevant adsorption pairs for all the International Union of Pure and Applied Chemistry (IUPAC)-classified adsorption isotherms are first selected for analysis

Read more

Summary

Introduction

To reduce global electricity demand, scientists are paying considerable attention to adsorption heat transformation (AHT) technologies such as cooling and heating as they can be driven by renewable energy or waste heat having a temperature of as low as 60 ◦ C [1]. It is found that different pairs exhibit different types of adsorption isotherms, and numerous authors had tried to get the best-fitted model for those [17]. Parameter effect adjustment and information loss are considered in this investigation to find the optimal isotherm model for a particular type, which makes it significant from the statistical analysis of the best-fitting model. 13 relevant isotherm data of “adsorbent-adsorbate” pairs are extracted from the literature for identifying optimal models for IUPAC classified eight types of isotherms. Statistical information criteria using a bootstrap sample have been used to select the optimal isotherm model for all IUPAC classified adsorption isotherms. Overall and pairwise proportion tests are conducted, for the equality of minimum information criterion, to identify the statistically significant optimal models for all types of IUPAC classified isotherms

Adsorption Isotherm Models
Tóth Model
Langmuir Model
Modified Langmuir Model
Freundlich Model
Hill Model
Mahle Model
2.10. Modified BET Model
2.12. Sun and Chakraborty Model
2.14. Ben Yahia Model
2.15. Universal Isotherm Model
Error Evaluation Function
Statistical Tools
Information-Based Criterion for Model Selection
Bootstrap Approach
Proportion Tests
Chi-Squared Test for Equality of Proportions
Pairwise Test
Results and Discussion
Bootstrap Error Analysis and Model Selection Using Information Criteria
Overall and Pairwise Proportion Tests
Type-II Adsorption Isotherm
Type-III Adsorption Isotherm
Type-V Adsorption Isotherm
Type-VI Adsorption
Conclusions

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.