Methyl methacrylate (MMA) is a specialty monomer for poly methyl methacrylate (PMMA) and the increasing demand for this monomer has motivated industry to develop clean technologies based on renewable resources. The dominant commercial process reacts acetone and hydrogen cyanide to MMA (ACH route) but the intermediates (hydrogen cyanide, and acetone cyanohydrin) are toxic and represent an environmental hazard. Esterification of methacrylic acid (MAA) to MMA is a compelling alternative together with ethylene, propylene, and isobutene/t-butanol as feedstocks. Partially oxidizing isobutane or 2-methyl-1,3-propanediol (2MPDO) over heteropolycompounds to MAA in a single-step is nascent technology to replace current processes. The focus of this review is on catalysts and their role in the development of processes herein described. Indeed, in some cases remarkable catalysts were studied that enabled considerable steps forward in both the advancement of catalysis science and establishing the basis for new technologies. An emblematic example is represented by Keggin-type heteropolycompounds with cesium and vanadium, which are promising catalysts to convert isobutane and 2MPDO to MAA. Renewable sources for the MMA or MAA route include acetone, isobutanol, ethanol, lactic, itaconic, and citric acids. End-of-life PMMA is expected to grow as a future source of MMA.

We report the gas-phase hydrogenolysis of glycerol to 1,3-propanediol over Pt/WO3/Al2O3in a fluidized bed operating above 240 °C and at ambient pressure.

Anthracite activated carbons are proper adsorbents for methane storage. In this study, Iranian local anthracite was activated using two commonly used chemicals (sodium hydroxide and potassium hydroxide) at similar conditions and their products are compared with regard to various properties in order to find the optimal operating parameters such as temperature, chemical ratio and pyrolysis time for producing ACs with high surface area. Three activation temperatures (670, 730 and 790 °C), three chemical-to-coal ratios (2, 2.5 and 3) and two pyrolysis times (1 and 2 hours) were studied in each carbon series (NaOH and KOH). Accordingly, the pore structures of Activated carbon (ACs) were investigated accurately based on adsorption isotherms of nitrogen as well as density functional theory. In addition, their methane storage capacities were also measured and discussed. Specific volumes (microporosity and mesoporosity) of products were also calculated. The KOH ACs had higher micropore volumes, whereas NaOH ACs had relatively higher densities. The highest methane storage was obtained by a KOH AC sample with 3:1 chemical-to-coal ratio (R), activated at 730 °C for 1 hour (AK37301). The stored and delivered methane for this sample were 176 and 158 vol/vol, respectively.

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BET surface area and micropore volume are important factors for improving methane storage in activated carbons (ACs). Specification and optimization of carbon structures are vastly examined by different researchers. However, because of complex relations between independent and dependent variables, the proposed statistical and mathematical models are not satisfactory. In this paper, the specifications of some ACs synthesized by chemical activation methods are predicted. The effects of parameters such as agent type, activation time, activation temperature, impregnation ratio and heating rate on the BET surface areas and micropore volumes of ACs are also analyzed. Two models of artificial neural networks and adaptive neuro-fuzzy interference systems are used. Later on, a number of data on other ACs reported by several researchers are used for the model validation. The obtained results from these two models are found to be satisfactory. The coefficients of determination for these models were 0.982 and 0.984, respectively. Through this modelling of AC production process, which was the main purpose of this study, the specifications of ACs may be obtained without spending extra time and expenses.