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In-situ catalytic pyrolysis has simple process configuration and low cost. Ex-situ catalytic pyrolysis can optimize the pyrolysis capacity and upgrade catalysis, and the catalytic can be reused. But there have been few studies researched on compare in-situ and ex-situ catalytic pyrolysis of the OS performed in similar reactor with two kinds of catalytic. This paper study the pyrolysis of oily sludge (OS) uses CaO and oily pyrolysis char as catalytic at 700 °C. Through analysis the pyrolysis oil (PO), pyrolysis solid (PS) and pyrolysis gas (PG) during pyrolysis procedure to research the difference between in-situ and ex-situ catalytic pyrolysis. The gas chromatography-mass spectrometry (GC-MS) results show that CaO was conducive to the synthesis of aromatics, which content more than aliphatics and heterocyclics in CaO-i (i: in-situ) and CaO-e (e: ex-situ) groups. However, char greatly inhibits the production of aromatic compounds and promotes the production of aliphatic compounds. Gas chromatography (GC) results present that the char and CaO can greatly increase the content of combustible gas and the content reach to 85.85%, the pyrolysis gas (PG) keep at the highest combustion performance in char-CaO-i group. Meanwhile, compared with uncatalyzed groups, the content of CH4 and CO increased about 2.05% and 3.93%, respectively. Fourier transform infrared spectroscopy (FT-IR) show that char and CaO reduce the function groups number of pyrolysis solid (PS), and it shows that the pyrolysis reaction is more complete. This research is expecting to provide theory support for catalytic pyrolysis of OS.

Aimed to obtain high-quality pyrolysis liquid products, the effects of different calcium-based catalysts and temperatures on liquid products from catalytic pyrolysis of municipal sludge (moisture of 50%) were studied. Results showed that the liquid product yield reached maximum at 600 °C and then decreased. The catalyst capability of catalysts decreased the yield of liquid products in the order of poorly soluble in water (Ca(OH)2, CaCO3, CaO) > soluble in water (CaCl2, Ca(H2PO4)2·H2O). High temperature strengthened the aromatization, and the breaking of the oxygen-containing functional group in liquid products resulted in the decrease of O/C and H/C molar ratios and the increase of four components yield in gaseous products. At 600 °C, the catalysts significantly reduced the O content of liquid products and increased hydrocarbon content. Meantime, CaO additive increased the content of C to 85.34%, and the relative content of aromatics reached 83.99% at 800 °C, which is suitable as chemical raw materials. However, the Ca(OH)2 group had the highest aliphatics content, and the H/C molar ratio was 1.42 at 400 °C, which is suitable as fuel.

The traditional preparation method of silicon monoxide (SiO) electrode is suffer from easy to agglomerate, rigour synthesis conditions and high cost, which seriously impede its application in power battery. In order to restrain aggregation or cake of powder particles during heating reaction and improve the dispersion performance of SiO powders, we adopt a novel fluidization thermal chemical vapor deposition (FTCVD) synthesis strategy. The strategy of this study is carried out in a kilogram-scale fluidization bed reactor. This approach is simple, manageable, inexpensive and scalable-productive, which can use for a large-scale production and commercial application. Here, the SiO@C composite through low cost micron-scale SiO powders as raw material no further grinding. The SiO@C anode material shows a high capacity of 501 mAh g−1 after 300 cycles at a current density of 1.2 A g−1, and an initial coulomb efficiency of 82% and high capacity retention of 93.3%. The new method can be applied to a large-scale production and commercial application.

Aging is inevitable when biochar uses for remediate Cadmium (Cd) pollution, but the variation of adsorption mechanism remains unclear. This study uses ramie residue to prepare fresh biochar, and adopt it with acidification and oxidation to simulate the aging process. The difference of physicochemical properties between fresh and aged biochar are studied through microstructure. Then, two kinds of biochar are making adsorption experiments in Cd solution for analyzing their adsorption mechanism. The results show that, both chemisorption and physisorption are exist, chemisorption and physisorption is the predominant way of fresh biochar and aged biochar respectively. Cation exchange is important but weaker in aged biochar than fresh biochar. Carboxyl plays a leading role in complexation of fresh biochar and hydroxy in aged biochar. Coprecipitation and cation-π mechanism impair apparently in aged biochar. This study indicates that aging change ramie biochar's main adsorption mechanism and the primary chemisorption way.

Pyrolysis is a research hotspot for realizing Chinese Herb residue (CHR) treatment and resource utilization, but there is little reported about in-situ no support catalytic pyrolysis of CHR. In this work, kinetics and no support catalytic pyrolysis characteristics of CHR were studied using a thermogravimetric analyzer and a fix-bed reactor system, respectively. Three groups: Ni-Fe, Ni-Cu and Ni-Co add into CHR and three kinetic methods: Coats-Redfern (CR) method, Flynn-Wall-Ozawa (FWO) method and Distributed Activation Energy Model(DAEM)use for calculate the activation energy, then analyses the gas, bio-oil and char of CHR pyrolysis. The results show that, catalysts can reduce the pyrolysis reaction activation energy. In FWO and DAEM model, the reaction activation energy will increase sharply if the conversion over 0.7. Compare with no catalyst group, add catalyst can restrain gas generation but good for oil production and char formation. Meanwhile, the surface of char is smoother than no catalyst. After test the char, we find that, metals of Ni, Fe, Cu and Co almost enrich in char, which may reuse as catalytic. This study may provide a feasible direction for the industrial application of CHR.

An experiment aimed to link the extent of axial mixing in a special configuration bubble column reactor with different liquid properties (water, 10% K2CO3 solution, 20% K2CO3 solution, paraffine). The experimental results proved that, increase of liquid viscosity will delay the mean residence time and weaken gas axial backmixing. Increased surface tension leads to lower flow regime transition point and higher overall gas holdup. Surface tension is the dominant factor to influence of gas axial backmixing degree. A simple RTD model for homogeneous–heterogeneous regime is developed in the column of 0.1 m diameter and the corresponding correlation of gas axial dispersion coefficients is D ag = 0.8 u g 1.89 ( ρ L / ρ w ) 3.22 ( ( 1 − e g ) 4 / e g ) . The model is verified by experiments with air/water/paraffine system. Good agreement is found. As a byproduct, a non-empirical formula for gas holdup results, ɛg/(1−ɛg)4 = 0.579 (ugμ/σ)0.918 (μ4g/ρLσ3)−0.252. But both correlations cannot be available for K2CO3 solution with addition of small quantities of surface tension in pure liquid.