This paper gives a comprehensive review about the most recent progress in synthesis, characterization, fundamental understanding, and the performance of graphene and graphene oxide sponges. Practical applications are considered including use in composite materials, as the electrode materials for electrochemical sensors, as absorbers for both gases and liquids, and as electrode materials for devices involved in electrochemical energy storage and conversion. Several advantages of both graphene and graphene oxide sponges such as three dimensional graphene networks, high surface area, high electro/thermo conductivities, high chemical/electrochemical stability, high flexibility and elasticity, and extremely high surface hydrophobicity are emphasized. To facilitate further research and development, the technical challenges are discussed, and several future research directions are also suggested in this paper.

A review of graphene and graphene oxide sponge: material synthesis and applications to energy and the environment

In this work, spongy graphene (SG), a shape-mouldable and nanoporous material with a high specific surface area used as a versatile and recyclable sorbent material, is proposed and studied. SG shows highly efficient absorption of not only petroleum products and fats, but also toxic solvents such as toluene and chloroform (up to 86 times of its own weight), requiring no further pretreatment, which is tens of times higher than that of conventional absorbers. Moreover, SG can be regenerated (>10 times) by heat treatment, yielding the full release of adsorbates (>99%). The present work suggests SG a widespread potential for applications in industry as well as topics regarding environmental protection.

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Spongy Graphene as a Highly Efficient and Recyclable Sorbent for Oils and Organic Solvents

Twisted carbon fiber (TCF) aerogel with good selective sorption is produced in large scale by using raw cotton as the precursor. TCF aerogel shows highly efficient sorption of organic liquids (pump oil: up to 192 times its own weight; chloroform: up to 115 times its own weight). Moreover, it could be regenerated many times without decrease of sorption capacity by distillation, combustion or squeezing, which depends on the type of pollutants.

Carbon Fiber Aerogel Made from Raw Cotton: A Novel, Efficient and Recyclable Sorbent for Oils and Organic Solvents

Compressive graphene aerogels were obtained by the one-step reduction and self-assembly of graphene oxide with ethylenediamine and then freeze-drying. The aerogels hold good compressibility, variable electrical resistance and fire-resistance. The high porosity with a hydrophobic nature, allows the aerogels to absorb different organic liquids, and the absorption–squeezing process has been demonstrated for oil collection.

Ultra-light, compressible and fire-resistant graphene aerogel as a highly efficient and recyclable absorbent for organic liquids

Most applications in energy storage devices revolve around the application of graphene. Graphene is capable of enhancing the performance, functionality as well as durability of many applications, but the commercialization of graphene still requires more research activity being conducted. This investigation explored the application of graphene in energy storage device, absorbers and electrochemical sensors. To expand the utilization of graphene, its present limitations must critically be addressed to improve their current performance. Again, in terms of applications, the advantages of graphene has widened their application in both electroanalytical and electrochemical sensors. These good characteristics of graphene must be extended further and improved to make them suitable for other applications. Critical study of facile synthesis of graphene coupled with detailed investigation into the structure of graphene oxide at the molecular level will equally improve the performance of this novel material. Effects of defects on the performance of graphene oxide was also identified as another key area of research that needs much attention to accelerate the commercialization of this material. With the rapid growth in the application of the graphene in different energy storage/conversion applications, it is essential to summarize and discuss the up-to-date progress in the application of graphene in these fields.

Application of graphene in energy storage device – A review

Study of oil sorption by expanded perlite at 298.15 K

During the past decades, a significant increase occurred in accidental oil spill in the aquatic environments. In this regard, oil spill in Marine freshwater is still considered as a major environmental hazard. In this research, the experimental data on the sorption capacity of expanded perlite to crude oil were correlated with the equilibrium isotherm of Langmuir, Freudlich, Tempkin and the three parameter Redlich-Peterson isotherms. The results obtained from each specified isotherms were compared and accuracy of the models were favorably discussed. Accuracy of each model using the error function were evaluated. Moreover, the effect of type of objective function on the final results was investigated. To bring up the idea; the sum of square of the average squares of the errors, the sum of the squares of the errors, the hybrid fractional error function, Marquardt’s percent standard deviation and Chi-Square objective function were used and the accuracy was obtained using each objective function. The results showed that the Redlich-Peterson model can better represent the equilibrium isotherm data for the crude oil to be up taken on the expanded perlite.

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Equilibrium sorption of crude oil by expanded perlite using different adsorption isotherms at 298.15 k

Effect of synthesizing conditions on the activity of zinc-copper aluminate nanocatalyst prepared by microwave combustion method used in the esterification reaction

In this study, a refrigeration cycle was simulated with different refrigerants in a petrochemical plant in Iran. Using Aspen HYSYS Software, necessary modifications were checked as much as possible and optimum values for important parameters affecting cycle of the optimized simulators in the Aspen HYSYS were found. Having found the most economical refrigeration cycle, financial expenses were reduced in the refrigeration cycle. Then, results from the simulation by Aspen HYSYS and Icarus software were compared with actual values of the petrochemical plant under study, and the most efficient and economical strategies to achieve the desired cycle were suggested. Energy consumption of the compressors was optimized by creating a Joule–Thomson balance between VLV-100 and the compressor power of the refrigeration cycle, which reduces the cost of utilities in the refrigeration cycle. The aim of this study is process optimization of the refrigeration cycle economically and also use of the environmental friendly refrigerants.

Performance analysis and development of a refrigeration cycle through various environmentally friendly refrigerants

Application of response surface methodology to optimize high active Cu-Zn-Al mixed metal oxide fabricated via microwave-assisted solution combustion method

Afshar Alihosseini

Papers

Study of oil sorption by expanded perlite at 298.15 K

Equilibrium sorption of crude oil by expanded perlite using different adsorption isotherms at 298.15 k

Effect of synthesizing conditions on the activity of zinc-copper aluminate nanocatalyst prepared by microwave combustion method used in the esterification reaction

Performance analysis and development of a refrigeration cycle through various environmentally friendly refrigerants

Application of response surface methodology to optimize high active Cu-Zn-Al mixed metal oxide fabricated via microwave-assisted solution combustion method