Abstract—Magnesium wastes and scraps, one of the metal wastes, are produced by many industrial activities, all over the world. Their growing size is becoming a future problem for the world. In this study, the use of magnesium wastes as a raw material in the production of the magnesium borate hydrates are aimed. The method used in the experiments is hydrothermal synthesis. The conditions are set to, waste magnesium to B 2 O 3 , 1:3 as a molar ratio. Four different reaction times are studied which are 30, 60, 120 and 240 minutes. For the identification analyses X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Raman spectroscopy techniques are used. As a result at all the reaction times magnesium borate hydrates are synthesized and the most crystalline forms are obtained at a reaction time of 120 minutes. The overall yields of the production are found between the values of 65-80 %. Keywords—Hydrothermal synthesis, magnesium borates, magnesium wastes, boron oxide I. INTRODUCTION HE increase in the rate of waste formation will be a problem for future of the world due to storage and disposal of wastes. In recent years, studies about waste storage and evaluation are done to solve this problem. Some kinds of waste are hazardous for people and environment. One of the dangerous wastes is metal wastes and scraps. Distribution of waste per person in the United States and Turkey are 8.9% and 7% of metal waste, respectively [1]. Evaluation of wastes is getting more interesting for industrial activities more than storage because of the increasing cost of raw materials and energy. One of the evaluation method is recycle process. Steps of metal waste recycling process are a separate collection, magnetic extraction, smelting factory, recycled metal, comprises the steps of the new metal products. Metal wastes are 1% of solid wastes and 3% of the recovered waste [2]. Magnesium wastes and scraps are produced by many industrial activities, all over the world. Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. Elemental magnesium is a fairly strong, silvery-white, light- weight metal (two thirds the density of aluminum). It tarnishes slightly when exposed to air. A. S. Kipcak, is with the Yildiz Technical University, Department of Chemical Engineering, Davutpasa Campus, 34210 Esenler, Istanbul, Turkey (phone: 0090-212-3834751; fax: 0090-212-3834725; e-mail: skipcak@ yildiz.edu.tr / seyhunkipcak@gmail.com). F. T. Senberber, is with the Yildiz Technical University, Department of Chemical Engineering, Davutpasa Campus, 34210 Esenler, Istanbul, Turkey (e-mail: tsenberber@gmail.com). E. Moroydor Derun, is with the Yildiz Technical University, Department of Chemical Engineering, Davutpasa Campus, 34210 Esenler, Istanbul, Turkey (e-mail: moroydor@yildiz.edu.tr / moroydor@gmail.com). S. Piskin, is with the Yildiz Technical University, Department of Chemical Engineering, Davutpasa Campus, 34210 Esenler, Istanbul, Turkey (e-mail: piskin@yildiz.edu.tr). It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole Magnesium is the fourth most common element in the Earth as a whole (behind iron, oxygen and silicon), making up 13% of the planet's mass and a large fraction of planet's mantle [3]-[5]. Boron is the chemical element with atomic number 5 and the chemical symbol B. The atomic mass is 10.81. It is a low- abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the water- solubility of its more common naturally occurring compounds, the borate minerals such as boric acid and borax. Turkey has 72.2% of the boron minerals that are present in the world, which can sufficiently meet world’s needs for many years. Approximately world’s total reserves are reported to be 1.2 billion tons [6], [7]. Boric acid, also called hydrogen borate having chemical formula H 3 BO 3 , is a weak acid of boron often used as an antiseptic, insecticide, flame retardant, as a neutron absorber, and as a precursor of other chemical compounds. It exists in the form of colorless crystals or a white powder and dissolves in water. Sometimes written B(OH) 3 . When occurring as a mineral, it is called sassolite [8]. Boron oxide can easily be formed from the following reaction: O(g) H (s) O B s BO H 2 3 2 3 3 3 ) ( 2 + → (1) Magnesium borate production is useful because of minerals superior properties of thermal and mechanic characters. Main properties of magnesium borate minerals are high heat resistance, corrosion resistance and high coefficient of elasticity. So this boron group can be used in ceramic industry, in the production of superconducting materials, in the composition of detergents, due to the content of boron in the friction-reducing additives in oils and insulating coating compositions [9]. Magnesium borates can be synthesized by liquid-state or solid-state methods. In literature, synthesized magnesium borate minerals with liquid-state method can be listed MgBO 2 (OH) [10], MgO.3B 2 O 3 .17H 2 O [11], MgO.3B 2 O 3 .3,5H 2 O [12], 2MgO.2B 2 O 3 .MgCl 2 .14H 2 O [13], 2MgO·B 2 O 3 ·H 2 O and MgO·3B 2 O 3 ·7H 2 O [14]. Synthesized magnesium borate minerals with solid-state method can be listed Mg 2 B 2 O 5 [15]–[17], Mg 3 B 2 O 6 [18], [19]. The common feature of all studies done as a raw material MgO or MgOH is to use in synthesis. In this study, magnesium wastes are used as magnesium source in magnesium borate production. It can be called as a new perspective in evaluation of metal wastes. A. S. Kipcak, F. T. Senberber, E. Moroydor Derun, S. Piskin Evaluation of the Magnesium Wastes with Boron Oxide in Magnesium Borate Synthesis T World Academy of Science, Engineering and Technology International Journal of Materials and Metallurgical Engineering Vol:6, No:7, 2012 616 International Scholarly and Scientific Research & Innovation 6(7) 2012 ISNI:0000000091950263 Open Science Index, Materials and Metallurgical Engineering Vol:6, No:7, 2012 publications.waset.org/2151/pdf