There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Elements Of X Ray Diffraction

Spectroscopy is the study of matter interacting with electromagnetic radiation (e.g., light). The electromagnetic spectrum in Figure 1 illustrates the many different types of electromagnetic radiation, including gamma rays (γ-rays), X-rays, ultraviolet (UV) radiation, visible light, infrared (IR) radiation, microwaves, and radio waves. The frequency (ν) and wavelength (λ) ranges associated with each form of radiant energy are also indicated in Figure 1.

Introduction to Spectroscopy

The past decade has seen a boom in environmental adsorption studies on the adsorptive removal of pollutants from the aqueous phase. A large majority of works treat kinetic modeling as a mere routine to describe the macroscopic trend of adsorptive uptake by using common models, often without careful appraisal of the characteristics and validity of the models. This review compiles common kinetic models and discusses their origins, features, modified versions (if any), and applicability with regard to liquid adsorption modeling for both batch adsorption and dynamic adsorption systems. Indiscriminate applications, ambiguities, and controversies are highlighted and clarified. The appropriateness of linear regression for correlating kinetic data is discussed. This review concludes with a note on the current scenario and the future of kinetics modeling of liquid adsorption.

Insight into the adsorption kinetics models for the removal of contaminants from aqueous solutions

Several industries are using dyes as coloring agents. The effluents from these industries are increasingly becoming an environmental problem. The removal of dyes from aqueous solution has a great potential in the field of environmental engineering. This paper reviews the classification, characteristics, and problems of dyes in detail. Advantages and disadvantages of different methods used for dye removal are also analyzed. Among these methods, Fenton process-based advanced oxidation processes are an emerging prospect in the field of dye removal. Fenton processes have been classified and represented as “Fenton circle”. This paper analyzes the recent studies on Fenton processes. The studies include analyzing different configurations of reactors used for dye removal, its efficiency, and the effects of various operating parameters such as pH, catalyst concentration, H2O2 concentration, initial dye concentration, and temperature of Fenton processes. From the present study, it can be conclude that Fenton processes are very effective and environmentally friendly methods for dye removal.

Degradation of dyes from aqueous solution by Fenton processes: a review

The present study proposed the use of Chir pine leaves ( Pinus roxburghii ) to remove As(V) ions from aqueous solutions. The influence of different sorption parameters such as the adsorbent dose, solution pH, contact time, agitation speed, and initial arsenic concentration were studied thoroughly to evaluate optimum conditions. Maximum adsorption has taken place at pH 4.0 while equilibrium was achieved in 35 min. Langmuir, Freundlich, Temkin, Elovich, Dubinin–Radushkevich and Flory–Huggins isotherm models were used to explain the phenomenon. Maximum adsorption capacity of P. roxburghii was 3.27 mg/g that was compared with the capacities of some previous adsorbents used for arsenic removal. Heat of sorption was close to 50 kJ/mol. Adsorption mechanism was explored by Pseudo first- and second-order kinetic models, and it was found that the process followed second order kinetics. The study concluded that the Chir pine leaves can be a good adsorbent for removing As(V) from water owing to the fine adsorption capacity.

Removal of arsenic from water using pine leaves

Microwave chemistry: Effect of ions on dielectric heating in microwave ovens

The adsorption of Cr (III) from water by polyaniline composites with rice husk and saw dust of Eucalyptus camaldulensis has been investigated in this study. The surface of adsorbents was characterized by FT-IR. Effect of various operational conditions like agitation time, initial pH, adsorbent dose, particle size of composites and temperature were studied in batch mode. The suitability of the data was confirmed by Langmuir and Freundlich isotherms. Thermodynamic studies showed that adsorption of Cr (III) on these composites occur spontaneously. Rice husk and saw dust modified the morphology of polyaniline by preventing its aggregation and improving its adsorption capacity.

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Isothermal and thermodynamical modeling of chromium (iii) adsorption by composites of polyaniline with rice husk and saw dust

The aim of this study is to check the feasibility of Psidium guajava (Guava) leaves and peels of Solanum tuberosum (Potato) as biosorbents in removal of Brilliant Green (BG) in batch mode. Surface analysis of biosorbents was done by FT-IR and quantitatively analyzed by Boehm titration. The removal of dye was confirmed by UV-VIS spectroscopy. Isothermal modeling was studied by using Langmuir, Freundlich, and Temkin isotherms. Various isothermal parameters for adsorption of Brilliant Green such as  mg/g, 1.173 mg/g , and −2.397 KJ/mol were noted for Solanum tuberosum peels (PP) and Psidium guajava leaves (GL), respectively. Similarly pH, moisture content, and various metals were quantitatively analyzed. Results showed that leaves of Psidium guajava were more effective for removal of Brilliant Green.

/pdf/brilliant-green-dye-elimination-from-water-using-psidium-58ib4xot4c.pdf

Rabia Rehman

Papers

Removal of arsenic from water using pine leaves

Microwave chemistry: Effect of ions on dielectric heating in microwave ovens

Isothermal and thermodynamical modeling of chromium (iii) adsorption by composites of polyaniline with rice husk and saw dust

Brilliant Green Dye Elimination from Water Using Psidium guajava Leaves and Solanum tuberosum Peels as Adsorbents in Environmentally Benign Way

Use of Agro-waste Musa acuminata and Solanum tuberosum peels for economical sorptive removal of Emerald green dye in ecofriendly way