| The energy demand of modern industrial society is mainly dependent on fossil fuels, which leads to the increase of greenhouse gases and other environmental problems. How to reduce the emissions of greenhouse gases and the use of greenhouse gases has become the focus of research. Carbon dioxide reforming with methane to synthesis gas is a very promising way of reducing greenhouse gas emissions and recycling. Two major greenhouse gases (CH4 and CO2) in the reforming process is converted to the synthesis gas (H2/CO=1/1) that suitable for FT synthesis and carbonyl synthesis in organic synthesis; convenient for storage and transportation of energy; has a great significance in natural gas comprehensive utilization. To a certain extent, it can provide a new way for alleviating the pressure of environment and energy.Copper slag is waste generated in matting smelting and matte blowing. Copper slag containing Fe, Cu, Zn, Co and Ni and other valuable metals, as well as SiO2, Al2O3, CaO and MgO oxides, it can be used as a natural catalyst for carbon dioxide reforming with methane. At the same time, copper slag containing plenty of waste heat resources, When copper slag is cooled from 1500℃ to room temperature, the energy release is about 1500kJ/kg. The heat released per ton slag is about 51kg standard coal. The reaction of carbon dioxide reforming with methane is a strong endothermic eaction, copper slag can be used as a catalyst in reforming reaction, but also provide heat for the reforming reaction.Because copper slag has a dense non-porous structure, and the active component content is low and mostly in the form of oxides, resulting in lower catalytic activity. So in this paper, the modification of copper slag was studied:copper slag was roasting modified to increase its surface area; dipping the calcined copper slag with nickel; melting copper slag with nickel. Using XRD, BET, H2-TPR, TG, SEM, EDS and other analytical testing characterization analysis copper slag before and after modification. The results show that calcined copper slag BET specific surface area greater than the untreated copper slag and active component in calcined copper slag is easier reduced by H2. The specific surface area of the copper slag melting with nickel is higher than impregnation method, and the active components in it isbetterdispersion.In this paper, the carbon dioxide reforming with methane is in a fixed bed reactor, at the conditionsof temperature in the range of 650～1000℃, feed gas ratio of CH4:CO2=1:1, space velocity (GHSV) of 300～2100m L/(h·g), the reactor internal pressure (P) is 1atm. Exploring influence of temperature and space velocity on the copper slag catalytic activity; and investigated the copper slag catalyst’s short time stability under the optimal conditions of temperature and space velocity. Experimental results show that the modified copper slagcarried with nickel having a more substantial improvement compared to the no modification copper slag catalytic.when the reaction temperature is 1000℃, and reaction space velocity is 300mL/(h·g), the conversion rate of CH4 and CO2 on Ni10/CCS950-I catalytic reached 82.8% and 80.2%, Ni10/CCS-S reached 71.8% and 68.3%. While in 6h short time stability testing, CCS, CCS950, Ni10/CCS950-I, Ni10/CCS-S were no significant deactivation.Through simulation experiments we study the copper slag waste heat catalyze carbon dioxide reforming with methane to synthesis gas. The catalytic activity of copper slag in the continuous cooling process and catalytic properties at different temperature points were assessment, by XRD, SEM, EDS and other means of material analysis. When the reaction temperature is 1200℃, conversion of CH4 and CO2 is 87.5% and 85.2%. when the reaction temperature was lowered to 600℃ CH4 and CO2 have the conversion of 6.8% and 5.9%. Finally, a kinetic equation about copper slag waste heat catalyzecarbon dioxide reforming with methane was established Experimental and theoretical basis was provided for the efficient cascade utilization of copper slag waste heat.
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