Experimental and theoretical study of industrial wastewaters containing some heavy metal ions by nano and nano-activated structures

Master's thesis in the field of mining chemistry

Abstract:

In this study, the effect of amide substitution on the surface of graphene oxide was studied. Two amines were chosen to change the contact surface and absorption rate. of a linear diamine such as ethylenediamine[1] and cyclic amine 6-aminouracil[2] with two different characteristics were evaluated. After the synthesis and identification of the products in the presence of copper, lead and cadmium metal ions in aqueous medium, the amount of absorption by each of the adsorbents was measured.

In this research, the aim is to improve the bonding properties of graphene oxide[3] by two types of amines. Addition of amine to graphene oxide creates an amide, and the graphene is somehow optimized and creates a compound with better properties for adsorbing metal ions at room temperature. Next, the effect of metal ion concentration, amount of adsorbent (weight) and time was investigated. Cu+2 ion shows better absorption than Pb+2 and Cd+2 ions by all three adsorbents. The adsorption rate of metal ions on each of the adsorbents has been observed as follows: Cu+2>Pb+2>Cd+2, so that the absorption process of ions on each of the adsorbents is the highest for copper metal ions. On the other hand, the desorption behavior of heavy metal ions on the surface of GO shows that GO can be reused after washing with HCl solution. This research shows that GO-ethylenediamine can be an effective adsorbent for the removal of toxic heavy metal ions from aqueous solutions. This investigation was also studied by the theoretical method. In the investigations carried out using Gossin software [4], the amount of stability energy, thermal energy and Gibbs free energy in two solvent and gas phases with the basis set g21-3 and (p,d)g31-6 were investigated for copper, cadmium, lead metal ions and nano adsorbents such as graphene oxide, 6-amino uracil and ethylene diamine. The results show that the stability and interaction of the copper metal ion is greater for surface adsorption [5] on the surface of ethylene diamine (due to its large functional group) and this adsorbent and absorbent can be used as a suitable filter to remove polluting metals.

Key words: optimized graphene oxide, adsorption of metal ions by graphene oxide derivatives, removal of metal pollutants, theoretical study

1-1- Introduction

Nowadays, nanotechnology has found a special place in the advancement of human knowledge, and discoveries in the nano field give new life to physics and chemistry. Nano science and technology is the ability to take control of matter in nanometer dimensions and exploit the properties and phenomena of this dimension in new materials, tools and systems, and it is actually a new approach in the production of products needed by humans. It seems that nanoscience and related sciences are not new. For hundreds of years, chemists have been using techniques in their work that are not dissimilar to today's nano techniques.

The path of evolution and formation of nano science in its current form began with the discovery of gold colloidal solution in 1857 by Faraday, and in 1959, Feynman proposed the idea of ??"a lot of space at low levels" for working with nanoscale materials. In 1974, for the first time, a word Nano technology was introduced by Taniguchi, and in the 1980s, this idea was studied in a wider way by Dr. Drexler. A scale nanometer is equivalent to one billionth of a meter (m9-10), which is one hundred thousand times smaller than the diameter of a human head hair, which is one tenth of a millimeter [1,2]. Nanoscale materials include materials whose dimensions are less than one micron in diameter. This size is approximately equal to the width of 3 to 4 atoms. The properties of materials with such dimensions and sizes are fundamentally different from conventional materials, and in this sense, research in the field of nanomaterials [2] is becoming more active day by day [3]. Since the properties of materials are strongly dependent on the size of the constituent components, i.e. the fine grains, the materials whose fine grains are designed on a nano scale have a new quality that cannot be found in ordinary materials [4].The importance of this length scale comes from the concept that from the point of view of quantum mechanics, the wave property of electrons inside matter and the interaction of atoms with each other is affected by the displacement of materials on the nanometer scale [6,5]. Nano[3] came to his tongue Noriya Taniguchi[4], a professor at Tokyo University of Science, used this term in 1974 to describe the manufacturing of precise materials whose dimensional tolerance is in the range of nanometers [8,7] [Nano technology is the application of particles in nano dimensions. In other words, the ability to produce new materials, tools and systems is by taking control at the molecular and atomic levels and using the properties that appear at those levels [9, 8]. [Intelligent manipulation and targeted control of materials at the atomic scale is considered the main goal of nanotechnology [10]. Therefore, nanotechnology is not considered a new field, but a new approach in all fields[9].

One ??of the important features of nanotechnology is its multidisciplinary aspect. In other words, almost all sciences are needed to understand the basic concepts and formulate laws in the nano scale. For example, biology is needed; Because firstly, nanotechnology products are highly dependent on biological systems, and secondly, nanoproducts have significant applications in biomedicine. Physics is needed, because the world of nano, the world of wave function, quantum tunneling and the discovery of unknown atomic forces is unknown. Chemistry is needed, because it teaches us the methods of linking molecules together and how to combine materials. Nanotechnology offers the following three principles:

Research and development of technology at the atomic, molecular and macromolecular (supermolecular) levels on a scale of about 1 to 100 nanometers [10].

Construction and use of structures, tools and systems that have new properties and functions due to their small or medium dimensions.

The ability to control or manipulate at the atomic scale] 8,7. What has caused the formation of nanotechnology is the emergence and unique properties on this scale. At the nano scale, objects begin to change their behavior and the behavior of surfaces overcomes the bulk behavior of matter. As a result, some physical relationships that apply to ordinary materials are violated.

As the scale of the material becomes smaller, the surface-to-volume ratio increases. Therefore, surface forces become more important. In fact, at this scale, the laws of quantum physics enter the scene and it will be possible to control the inherent properties of matter, including the melting point, magnetic properties, electrical properties, and even the color of the material, without changing the chemical composition of the material. A high surface-to-volume ratio will also increase reactivity, and nanoscale materials are more reactive. We will also have catalysts with higher efficiency.

1-5- The importance of nano technology

Nano technology is a new approach to science and technology and research, in other words, it is a fundamental look at the surrounding world from a molecular scale.

Analysts believe that nano technology, technology Biology[6] and information technology[7] are three scientific fields that form the third industrial revolution. The most important factor and the main driving force behind the growth of nanotechnology is its economic benefit. This new approach has its roots in the last fifty years and its traces can be seen in physical and chemical sciences [11]. In nanotechnology, we are able to produce structures that do not exist in nature [12].

Nanoscience and nanotechnology provides information about controlling the size of nanostructures, the size distribution of these materials and compounds, and how they are arranged. Some of the advantages of nanotechnology are the production of stronger materials and lower production costs