With the strong global increase in transportation technology and daily increase of cars, the interest in recycling of waste tires have been increased due to energy resources and environmental protection. One of the recycling methods for waste tires is pyrolysis and converting them into liquid fuels. In this study the effect of final reaction temperature and residence time on pyrolysis process and obtained liquid fuels were investigated. Among the pyrolysis products which are solids, liquids and gases, the liquids were selected for further investigation. These pyrolysis liquids were characterized by FTIR spectroscopy, and the results showed that liquids contain linear hydrocarbon more than 4 carbon moves toward aromatic component with increasing pyrolysis temperature. These findings were also confirmed by Detailed Hydrocarbon Analysis(DHA). The components of pyrolysis liquids consisted mainly of 2, 3-dimethylbutene, 2-Methylbutene, t-Isobutyl-4-ethyl-benzene, and 1-m-4Isopropyl-benzene. The results also showed that the percentages of gases and liquids were increased and decreased respectively with increasing of temperature but there is no change in char percentage yields above 500° C. It is Obviouse that the maximum amount of solids is equal to the percentage of carbon black and other minerals in the rubber formulation that remain in pyrolysis. Measuring of calorific value of pyrolysis liquids showed good compatibility with commercial heating fuels.

Waste tires left in the environment are now becoming a global problem. On the other hand, the use of minerals consumed in the construction industry, in addition to being expensive, may reduce the natural mineral reserves around us. Using waste tire powder to make Autoclaved Aerated Concrete (AAC) is cost-effective. The presence of rubber powder inside the AAC leads to the toughness of the concrete and increases the elongation at break, and gives the plastic behavior to the concrete. In this study, rubber powder of different sizes was used as a filler inside the autoclaved concrete. The presence of elastic rubber particles enhances the sound absorption of AAC. The results revealed that by changing the amount of aluminum added to the concrete mixture, the impact of rubber addition on the density of AAC could be controlled. Reducing the particle size of tire powder also increases the sound absorption of AAC.

Background and objective: It is a fact that demand for wood products has been increasing with the increasing in the population of the world that adversely influences the sustainable utilization of forest resources. In recent years, there has been widespread interest in the manufacturing of products from recycled materials. Among the waste materials, waste tires are a major concern, because the amount of waste tires is increasing more and more due to the increasing demand for tires and because of their short lifetime, it is therefore necessary to develop methods for recycling waste tires. Effectively recycling waste tires such as manufacturing wood-rubberbased composites could be one of the solutions. This research, physical and mechanical properties of particleboard made from waste tire powder and wood particles were investigated. Materials and methods: The variable in this research were the ratio of waste tire powder to wood chips (at five levels; 0: 100, 10: 90, 20: 80, 30: 70, 40: 60). Industrial wood particles from Sanate Choube Shomal Company were used. Urea formaldehyde resin used at 10 percent level of dry weight of raw material as well as ammonium chloride was used as a catalyst at 2 percent level of the dry weight of adhesive. After the mixing process raw material together, mat at temperature of 170° c for 5 minutes under hot press was placed. Physical and mechanical properties of panels measured according to EN Standard. Also the dispersion of waste tire in particleboard was evaluated by scanning electron microscopy (SEM). Physical and mechanical properties of panels analyzed using variance analysis in 5% probability level. Results: The results showed, increasing waste tire percent resulted in decreasing the bending strength, modulus of elasticity and internal bonding of the boards. Although melting of the tire might be expected to increase bonding strength with the wood, this did not happen at the temperatures applied in this study, because the waste tire might melt at temperatures higher than 170° c. Based on images of scanning electron microscopy, it is clear that tire has not melted at the press temperature and has been created no connection with wood. Water absorption and thickness swelling after 2 and 24 hours immersion in water decreased with increasing of the waste tire content, So that the maximum of WA and TS after 2 and 24 hours of immersion in water were found in control specimens and the minimum value of these factors were found in the boards contain of 40 percent of the waste tire. Conclusion: Results showed, there was usability of the waste tire up to 20 percent for general purpose boards and up to 10 percent for interior fitments (including furniture) for use in dry conditions.

One of the recycling approaches for waste materials like tires and glass is to use them in concrete. In this paper, the effect of the simultaneous use of waste rubber as partial substitution of fine aggregate and glass powder as partial substitution of cement, on workability and mechanical properties, in ambient temperature and after exposure to temperature of 600 °C, is investigated. In order to evaluate the effect of rubber particle size on workability and mechanical properties, two different rubber particle sizes of 0.15-1mm and 3-5mm were used. In total, 13 mixtures were prepared. Except for the reference mixture, the rest contained a combination of rubber particles replacing fine aggregate with the percentages of 5% and 10% by volume and glass powder replacing cement with percentages of 10%, 15% and 20%. First of all, the slump test was carried out. Moreover, compressive strength and tensile strength, before and after thermal exposure, were investigated. In order to have an understanding of waste material's behavior, scanning electron microscopy and energy-dispersive X-ray spectroscopy tests were conducted. the results indicated that 5% for rubber particles, 10% for glass powder and also rubber particle size of 3-5 mm presented the best results among mixtures containing rubber and glass powder, in terms of compressive and tensile strengths.

Today, the use of waste tires has been expanded in various geotechnical projects to absorb and reduce the vibration caused by seismic and dynamic loads, and therefore it is important to study the effect of different parameters on their behavior and dynamic characteristics in combination with soil. So this study examined the effects of loading frequency on dynamic properties of sand-tire powder mixtures such as shear modulus (G) and damping ratio (D). A series of 1-g shaking table tests were performed on sand-tire powder mixture. Tire powders were added to the sand with 5%, 10%, 15% and 20% in gravimetric basis and with a relative density of zero were subjected to sinusoidal loading at frequencies of 0. 5, 1, 2, 3, 5, 7 and 9 Hz and at input acceleration of 0. 1g and 0. 3g. The results showed that in all cases, the increase in frequency in the same cycles increased the shear modulus and the damping ratio. Also, with increasing shear strain, the shear modulus of the mixture decreased, but the damping ratio increased. On the other hand, by increasing the tire powder, the value of the shear modulus is reduced, but the amount of damping ratio is increased.

The limitation of fresh water resources in the most parts of the country has necessitated the use of unconventional water resources. Wastewater is one of these unconventional sources, however the environmental impacts of wastewater reuse should be carfully considered. The present study aimed to examine the effect of the rubber powder to absorb the heavy metals of lead, zinc and manganese in laboratory scale. The batch tests to evaluate the absorption equilibrium time were conducted in constant pH of 5.5 and the soluble metal concentration equal to 100 mg per liter. The adsorption kinetic results showed, the removal efficiency of lead, zinc and manganese were 67.2, 74.3 and 39.9 percent, respectively. Time to reach equilibrium for zinc and manganese were 180 and 120 minutes, respectively. But lead does not reach equilibrium during the 180 minutes of testing time. Also, the adsorption isotherms tests were performed for these metals and the data were fitted with the linear, Langmuir and Freundlich models. The results showed that the Freundlich adsorption model with regression coefficient equal to 99 percent was the best compliance with the laboratory results.

A rotated tire is affected by various forces and torques from the contact patch. On the other hand, the structure of the tire is very complex and tire is a complex combination. Each of these components can affect the forces and torques applied to the tire. These forces and torques also have a great effect on the handling of the car. In this paper, the apex height, the belt width, the belt angle and the capply type in a PCR tire are considered. The design of Experimental is based on Taguchi method which related to the apex height, the belt width, the belt angle and the capply type. Based on the design of experimental, 9 different tires have been made. The values of cornering stiffness obtained from the experimental and the effect of the mentioned factors on the cornering stiffness of the tire has been investigated.

Waste tire rubber (WTR) contain significant amounts of zinc (Zn) and they are potential sources of Zn for plants. This study was carried out to investigate the effect of Zn-dissolving Pseudomonas isolates and WTR on growth characteristics and Zn and Fe concentrations of the corn plant. An experiment was conducted in a completely randomized design with factorial arrangement with three replications in a sterile sand-culture in green house condition. The experimental factors include Pseudomonas bacteria at six levels (without inoculation (C) and inoculation with five isolates (B1 to B5)) and Zn treatment from the WTR source at four levels of 0 (C), 100 (T1), 200 (T2) and 300 (T3) mg Zn per kg (equivalent to 0, 9, 18 and 27 g WTR per kg of sand respectively). The results showed that the main effects of the treatments on Photosynthetic performance index, chlorophyll content of leaves, Chlorophyll fluorescence and shoot dry weight were significant. The amount of each of these parameters increased in all bacterial and WTR treatments. The use of WTR (18 g/kg) along with inoculation of isolates increased all measured parameters compared to the control. Root dry weight and zinc concentration in shoots and roots, were affected by the interaction of treatments. The highest amount of plant dry weight was observed in B3+T3 treatment (2. 14 fold increase compared to the control (. The concentration of zinc in the plant shoots was the highest in the B4+T3 treatment, which was 20 times higher than the control. The highest concentration of zinc in the root was observed in the presence of isolates B3 and B2 in WTR (18 g/kg) treatment which was 25 and 22 times higher than the control, respectively. The highest concentration of iron in the shoots and roots of the plant was related to the WTR (18 g/kg) treatment with the amount of 28. 3 and 30. 7 mg kg-1, respectively. The bacterial isolates increased the iron concentration of shoot compared to the control, but no significant difference was observed between the isolates.

In this study, three different size (100-300-500 µ m) of the rubber powder (waste tire) were used in the formulation of epoxy-phenolic adhesive. Rubber powder was modified with grafting method by acrylamide monomer. In order to prevent any loss in properties such as modulus and strength of the adhesive, which is due to the addition of rubber powder to the adhesive, the micro particles of silica were used in formulation of epoxy-phenolic adhesive. The experiment was designed by Taguchi method, and in the experiment, the effect of the composition of rubber powder, size of rubber powder, composition of silica filler and phenolic resin on mechanical and thermal properties of epoxy adhesives were investigated. To study the mechanical properties of adhesives and adhesion properties, dumbbell-shaped specimens and single edge lap bonds that have been made of metal (stainless steel) to composite (epoxy resin / carbon fiber) were prepared and subjected to tensile test. Thermal stability and interfacial interaction between epoxy and filler in adhesive formulation were explored by thermogravimetric analysis and Fourier transform infrared spectroscopy analyses, respectively. Tensile test results showed that for lap-joint bonding with the addition of each factor in its optimal level into epoxy adhesive, strength, modulus and toughness increase by 7. 5%, 27. 56% and 114% respectively in comparison with the samples bonded with the neat epoxy adhesive. A significant increase was obtained in thermal stability for formulated adhesive samples compared with neat epoxy adhesive.

Attempts to use waster rubber powder as an adsorbent of pollutants in wastewater treatment applications is an environmentally friendly, efficient and novel method, especially in the tire industry wastewater treatment process. This study evaluated the efficiency of waste tire rubber powder in adsorbing the tire industry wastewater. The rubber and The wastewater were prepared from Kavir Qom Co. and Artawheel Tire Co., respectively. Comparison of UV-vis spectrophotometer results of the nontreated wastewater with the wastewater data after adsorption under various thermal and temporal conditions indicated that the tire powder adsorbent has the necessary efficiency for treating the tire industry wastewater. Examination of data with pseudo-first- and second-order kinetic models also confirmed the adsorbent’s efficiency and showed that the second-order kinetic model had a good correspondence with the obtained results.