Abstract
“ADSORPTION STUDIES OF SOME METAL IONS AND ORGANIC
COMPOUNDS ON LOW COST MATERIALS.”
Introduction:In the 21st century environmental pollution is one of the major threats to
human life. Among the different types of pollution, waste water stream is one of the
major problems due to the fact that large amount of water used in our daily life. Waste
water quality can be defined by physical, chemical or biological characteristics; waste
water generally contains toxic inorganic and organic pollutants. Inorganic pollutants
consist of mineral acids, inorganic salts, finely divided metal compounds, trace
elements, cyanides, nutrients, and organometallic compounds. Waste water pollution
comes from the industrial effluents and also from the domestic sewage etc.
Environmental problems threatening not only to the aquatic ecosystems but also to the
human health through contamination of drinking water. The waste water contains
many hazardous materials. The presence of toxic heavy metal ions such as Ni (II), Cu
(II), Cr (VI), Zn (II), Fe (II), etc. in industrial waste water has attracted worldwide
attention. Most of heavy metal ions produce undesirable effects on human and animal
life even present in low concentration. Heavy metal ions are non- degradable and
cannot be converted into non toxic end products. Their concentrations must be
reduced to acceptable levels before discharging them into environment otherwise they
are dangerous to public health and affect the aesthetic quality of potable water.
According to World Health Organization (WHO) the metals of most immediate
concern are Ni (II), Cu (II), Cr (VI), Zn (II), Fe (II), Pb (II), etc.
Similarly there are certain organic compounds and dyes used in textile,
pharmaceuticals, electroplating and other industries. The textile industry, a major
consumer of water, also a major producer of effluents. Waste water containing
organic surfactants, salts, acids, alcohols and dyes as some of its main constituents. In
fact of the commercially used dyes are present to biodegradation, photo degradation
and even oxidizing agents. Adsorption is effective and cheap method for the removal
of such chemicals. A low cost material has been used to remove heavy toxic metal
ions and organic compounds from water.
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Abstract
The present work is to study the removal of Congo red, crystal violet and
Methylene blue dyes as well as Cr (VI), Cu (II) and Ni (II), metal ions by adsorption
technique using agricultural adsorbents from dicotyledonous crop seeds husk such as
husk of gram seeds (GSH), husk of red gram seeds (RGSH), husk of green gram seeds
(GGSH), husk of black gram seeds (BGSH), husk of pea seeds (PSH), husk of masoor
seeds (MsSH), husk of mattki seeds (MtSH), husk of chawali seeds (CSH), and husk
of lakh seeds (LSH). The main advantage of this agricultural low cost materials are
that they are very cheap, easily available in excess quantities eco-friendly and hence
used to removal Ni (II), Cu (II) and Cr (VI), heavy metal ions and Methylene blue,
crystal violet and Congo red dyes from aqueous water.
Batch experimental method was used for present investigation. The effect of
contact time, effect of initial concentration, effect of adsorbent dose, effect of
temperature, effect of salt, effect of pH and zero point pH etc. were carried out. The
validity of Langmuir and Freundlich adsorption isotherms was checked. The
adsorption kinetics also checked by using pseudo-first order kinetic model and
pseudo-second order kinetic models. Thermodynamic parameters such as Gibb's free
energy change
, enthalpy change
and entropy change
were calculated by
using Van’t Hoff’s equation.
The present work was submitted in the form ‘of thesis entitled “Adsorption
studies of some metal ions and organic compounds on low cost materials.” It is
divided into four chapters.
Chapter I: Introduction
It deals with the brief introduction of the adsorption phenomenon, basic
principles involved in adsorption different theories of adsorptions and factors
affecting the adsorption have been discussed in present work. It gives detailed account
of different methods that used in adsorption. This chapter also covers literature survey
and previous reported work. The chapter concludes with the aims and objectives of
the work and references.
Chapter II: Experimental Details
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Abstract
It gives detailed description of experimental works, materials and methods
used.
Procedure
involved
calibration
of
instruments
(pH
meter,
UV-
Spectrophotometer) and calibration of volumetric apparatus etc. It also covers
preparation of solutions and reagents required for experiments.
Chapter III: Experimental Results
Adsorption of a basic dyes i.e. Congo Red (CR), Crystal Violet (CV) and
Methylene Blue (MB), as well as heavy metal ions i.e. Cr6+, Cu2+, and Ni2+ from
aqueous solutions by using different low cost materials as adsorbents was
investigated. The effects of contact time, pH, Initial concentration, temperature,
addition of salt (KCl), etc. were investigated. The results were analyzed to find out
thermodynamic and kinetic parameters. Different adsorption isotherms were also
tested.
Chapter IV: Discussion
This chapter concludes the results obtained from experimental data and well
represented in the form of graph. The effect of various operating conditions like
contact time, adsorbent dose, initial concentration, temperature, initial pH of dye as
well as metal ions solution and amount of KCl were investigated. The percentage
adsorption efficiency of dyes and increased with increasing adsorbent dosage, contact
time, initial concentration of dyes solution while was decreased with increasing
temperature, initial pH of solution and amount of KCl. The adsorption equilibrium
was attained after 24 hours. The adsorption process follows by pseudo second order
rate model better than a pseudo first order rate model. The negative value of
and
showed the adsorption is exothermic nature and a decrease in disorder of dyes as
well as metal ion molecules in the adsorption process respectively. The
value
showed that the adsorbents were favorable for the adsorption of dyes and heavy metal
ions. The results of investigation showed that all adsorbents have considerable
potential for the adsorption of dyes and metal ions from aqueous solution and may be
used as a low cost natural and abundant source for the adsorption of dyes and they
may be alternative to more costly materials, It may also be effective in adsorbing as
well as other harmful or undesirable species such as heavy metals, dyes, and other
hazardous pollutants present in waste effluents. The result of this study indicates that
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Abstract
all adsorbents can be successfully used for the adsorption of dyes from aqueous
solution.
The references are quoted at the end of each chapter. The list of papers
communicated and published is enclosed at the end of chapter IV.
The chapter is divided into subsections that represent the work done on different dyes.
Research Student
Research Guide
Jirekar Dattatraya Babasaheb.
Dr. Mazahar N. Farooqui
Dr. Rafiq Zakaria College for Women,
Aurangabad-431004(MS).
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