A catalytic system over Ru-HAP catalyst is established to hydrodeoxygenate various oils to long-chain alkanes in water, for potential large-scale renewable diesel production, which has the following advantages. (i) This system is versatile to different oil sources, including Jatropha oil, palm oil, waste cooking oil, and cooking waste. (ii) Ru-HAP is highly efficient at achieving full conversion from stearic acid to alkanes at as low as 100 °C, and the isolated yield from Jatropha oil, palm oil, and waste cooking oil to long-chain alkanes reached up to 95, 96, and 87 mol % at 180 °C and 2 MPa H2 within 4–4.5 h, respectively. (iii) The catalyst showed high stability during five runs of recycling, ICP-OES analysis, and a hydrothermal treatment. The activity decreased less than 5% after the catalyst was treated in water at 200 °C for 24 h with a stirring speed of 1000 rpm due to the strong metal and hydrothermally stable support interaction. (iv) Ru-HAP is compatible with most impurities such as various salts, sugars, and macromolecules. (v) The system required low cost for operation since no dehydration before the reaction was necessary and the alkane product can be easily separated from water. The reaction route was investigated and indicated that the coexisting hydrodehydration and hydrodecarbonylation are affected by water, temperature, and H2 pressure. The catalyst was also characterized in detail, and its high reactivity and stability may result from the fact that highly distributed Ru nanoclusters anchored on the HAP support absorbed fatty acids by forming a metastable calcium carboxyl phosphate.
Jinxi Zhang,Duowang Yang,Guoqiang Sun,Yiwen Li,Yue Qi,Xiaoyan Ma
Using recycled oils and chemical stabilizers as the additives in high-viscosity modified asphalt (HVMA) is being developed as a sustainable way to solve the severe segregation problems due to the large differences in nature between high-content styrene–butadienestyrene (SBS) and base asphalt. This paper attempts to use three recycled oils, namely castor oil (CO), waste cooking oil (WCO) and recycled engine oil (REO), as compatibilizers in combination with different chemical stabilizers (polyphosphoric acid, PPA; sulfur) to investigate their ameliorative roles on HVMA segregation problems. By means of the gel permeation chromatography, dynamic shear rheometer and fluorescence microscopy, the chemo-rheological properties and morphological structures of HVMA are investigated, as well as their storage stability. Results show that the recycled oils are more favorable to improve the high-temperature rheological performance of HVMA than aromatic oil (AO) by comprehensively considering the softening point, zero-shear viscosity, elastic recovery percent and large molecule percentage, and the role ranking is: REO > WCO > CO > AO. Compared with the addition of PPA or sulfur alone, when PPA and sulfur are added together, the rheological performance of HVMA is promoted most significantly, because of the synergistic cross-linking reaction of these chemical stabilizers with asphalt and polymers. Furthermore, the synergistic effect of PPA and sulfur markedly reduces the temperature sensitivity of HVMA. However, the cigar tube test reflects that adding recycled oils as compatibilizers alone can not improve the storage stability of HVMA, and CO and WCO even aggravate its segregation. Notably, adding REO and chemical stabilizers can markedly improve the storage stability of HVMA, and the effect is most obvious when REO, PPA and sulfur are added together.
Huifang Liu,Jianyu Han,Qitian Huang,Hongwei Shen,Lijun Lei,Zhipeng Huang,Zhixin Zhang,Zongbao K. Zhao,Feng Wang
Catalytic hydrotreating of renewable oils is a promising way to get diesel alkanes, with the use of microbial lipids further facilitating scalable production of green diesel. The core issue of triglyceride hydrodeoxygenation (HDO) research is still to develop efficient catalysts under mild reaction conditions. Herein, we demonstrate that the heteropolyacid (HPA)-modified SiO2 supported Pd catalysts showed high activity for the HDO reaction of methyl stearate and soybean oil to diesel alkanes (C15∼C18, >90 wt % at 200 °C). Characterizations show that the Brønsted acid sites introduced by grafting heteropolyacid on SiO2 and metal sites of small Pd particles contribute to the high HDO activity of this bifunctional catalyst. Additionally, lipids produced by Rhodosporidium toruloides Y4 from glucose or corn stover were also transformed to about 75 wt % of diesel-range alkane products. This integration of microbial lipid production with chemical catalysis should facilitate the engineering of green diesel production from lignocellulosic biomass.
危险品化学品经营许可证（带存储）