جستجوی مقالات مرتبط با کلیدواژه « اکسیدهای فلزی » در نشریات گروه « شیمی »

Domestic companies in metal and alloy production have faced many problems in providing the required energy. These companies often use traditional industrial furnaces, which consume a lot of energy, have a very negative impact on the environment. For this reason, the use of modern low-consumption processes for metal oxide reduction will be of great interest. In this research, the carbon bed of a new metal oxide reduction system operated under microwave heating is modeled. In this system, the carbon bed is responsible for the heating process and converts electromagnetic waves into heat. In this system, because the metal oxide granules are imbedded inside the carbon bed that converts almost all electromagnetic waves, the heating effects of metal oxides were ignored. Comparison of the modeling results with experimental data related to carbon bed temperature rising trend showed that the used model has good accuracy and the average error is less than 5%. Based on the modeling, it was found that the carbon bed temperature (excluding metal oxide granules) increased around 9% by increasing the microwave power from 1000 w to 1200 w. In addition, SiC had better performance compared to the carbon bed in terms of the rate of generated heat. It was determined that the maximum temperature decreased by increasing the carbon emissivity parameter and the final bed temperature increased by 9% after 15 minutes by changing the emissivity parameter from 0.95 to 0.65.

The electrochemical coagulation process, or EC, is an electrochemical process that direct electrical current was used to remove pollutants from solution. In this paper, the effect of nanofluids of iron, copper, and zinc metal oxides on electrochemical reaction of heavy cobalt metal removal from the refinery wastewater was investigated. Different tests were performed to achieve the best performance with maximum efficiency. In the meantime, the best performance was achieved at 30 volts and 60 minutes having efficiency up to 52%. In the next step, the tests were performed using iron, copper, and zinc nanoparticles oxides that they could been reduced cobalt values to 73%, 87% and 61% of the initial amounts, respectively. Between used metal oxides, the results show iron oxide nanoparticles could reached to maximum cobalt removal from the wastewater, and after that copper and zinc oxides nanoparticles have high removal efficiency, respectively. Surface response method used to determining the optimum cobalt removal conditions. A quadratic statistical model was presented in terms of experimental parameters. The statistical model predictions from experimental design are in good agreement with experimental data for cobalt removal in this work.