废弃ABS电视机外壳热解试验研究

研究了温度、时间以及催化剂对废弃丙烯腈-丁二烯-苯乙烯共聚物(ABS)电视机外壳热解及其产物的影响。结果表明,热解液体产物的收率随温度的升高和反应时间的延长而升高;同时,随温度的升高,液体产物中汽油和柴油的含量逐渐升高,而重油的含量逐渐降低。对比了氧化锌、三氧化二铁和FCC这3种催化剂对热解的影响。结果表明,采用FCC时热解液体产物的收率最高,同时FCC的加入使反应温度下降了100℃,使液体产物中汽油的含量增加了17.7%。通过对热解液体产物进行气相色谱-质谱联用分析可知,其主要成分及其质量分数分别是苯乙烯36.49%,4-苯丁腈为19.72%,α-甲基苯乙烯12.1%,乙苯9.69%。

固体废弃物资源化处理技术综述

随着全球人口的增长和经济的发展,固体废弃物产生量不断增加,给环境带来严重的挑战。为了实现可持续发展,有必要对固体废弃物进行资源化处理。目前,固体废弃物资源化处理技术主要有生物转化、热解裂解、气化等。本文结合固体废弃物资源化处理技术现状,分析不同技术的优势,指出面临的挑战,以期为固体废弃物处理提供理论参考。

煤层气分馏效应研究进展及其应用

煤层气自生成以来发生的组分分馏和同位素分馏,指示了煤层气成藏过程,这使得煤层气富集区预测成为可能。基于近年来国内外文献,将煤层气分馏划分为成因分馏和运移分馏两大类,并对各种分馏效应的研究进展情况进行了系统述评。同时论述了煤层气分馏效应的地质及工程应用现状,认为进一步探讨矿物在煤层气热解—裂解分馏中的作用和效应,培育能适应较高温度和压力且能高效利用CO2生成生物CH4的优良菌种,建立多种分馏效应共存的煤层气分馏综合效应模型,是近期本领域研究应努力的方向。

Effect of Catalyst Properties on Hydrocracking of Pyrolytic Lignin to Liquid Fuel in Supercritical Ethanol

The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore size and supported metal on hydrocracking of pyrolytic lignin in supercritical ethanol and hydrogen were investigated at 260 ℃. A series of catalysts were prepared and characterized by BET, XRD, and NHa-TPD techniques. The results showed that enhancing the acidity of the catalyst without metal can promote pyrolytic lignin poly- merization to form more solid and condensation to produce more water. The pore size of microporous catalyst was smaller than mesoporous catalyst. Together with strong acid- ity, it caused pyrolytic lignin further hydrocrack to numerous gas. Introducing Ru into acidic catalysts promoted pyrolytic lignin hydrocracking and inhibited the polymerization and condensation, which caused the yield of pyrolytic lignin liquefaction product to increase significantly. Therefore, bifunctional catalyst with high hydrocracking activity metal Ru supported on materials with acidic sites and mesopores was imperative to get satisfactory results for the conversion of pyrolytic lignin to liquid products under supercritical conditions and hydrogen atmosphere.

Study on the comparison of the pyrolysis gas release of lignite and its briquette

In this experiment, lignite was refined and processed through binderless briquette preparation process from low-rank coal and became briquette. Then, lignite and its briquette were pyrolysed as materials to compare the nature of their pyrolysis. In this study, the experiment was carried out through a lab tube furnace, at a heating rate of 10 ~C/min, and the gas was analyzed and compared, which was collected at different temperatures. The results show that： in the pyrolysis temperature of 550-850 ℃, the semi-coke yield of briquette is 2%-6% higher than lignite, the tar yield of briquette is 2%-3% higher than lignite and the gas yield of briquette is 4%-9% less than lignite. The time required for complete release of the briquette is about 20 min less than lignite. The components in the pyrolysis gas of lignite and its briquette are the same, and their variation with the pyrolysis temperature is similar.

Advances in study of dehalogenation of plastic waste by pyrolysis

Several methods ofdehalogenation by pyrolysis were summarized in this paper. Some crucial academic problems have been brought forward after analyzing and comparing the technical character as well as dehalogenation efficiency of these methods, which should be emphasized in the future research.

Simulation of hydrocarbons pyrolysis in a fast-mixing reactor

Currently, thermal decomposition of hydrocarbons for the production of basic petrochemicals(ethylene, propylene) is carried out in steam-cracking processes. Aside from the conventional method, under consideration are alternative ways purposed for process intensification. In the context of these activities, the method of hightemperature pyrolysis of hydrocarbons in a heat-carrier flow is studied, which differs from previous ones and is based on the ability of an ultra-short time of feedstock/heat-carrier mixing. This enables to study the pyrolysis process at high temperature(up to 1500 K) at the reactor inlet. A set of model experiments is conducted on the lab scale facility. Liquefied petroleum gas(LPG) and naphtha are used as a feedstock. The detailed data are obtained on temperature and product distributions within a wide range of the residence time. A theoretical model based on the detailed kinetics of the process is developed, too. The effect of governing parameters on the pyrolysis process is analyzed by the results of the simulation and experiments. In particular, the optimal temperature is detected which corresponds to the maximum ethylene yield. Product yields in our experiments are compared with the similar ones in the conventional pyrolysis method. In both cases(LPG and naphtha), ethylene selectivity in the fast-mixing reactor is substantially higher than in current technology.

On-Line Pyrolysis-Liquid Chromatography of （Meth-） Acrylic Acid in Waterborne Polymers Using Cryogenic Injection

Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chromatographic injector by means of cryogenic-focussing is developed to determine the presence and concentration of hydroxyl and carboxyl functional monomers present in water- and solvent-borne acrylics. We have shown the prove-of-principle of using cryogenic-focussing for UPLC （pyrolysis-ultra-performance liquid chromatography） injection.

Experimental and Modelling Studies of Biomass Pyrolysis

The analysis on the feedstock pyrolysis characteristic and the impacts of process parameters on pyrolysis outcomes can assist in the designing,operating and optimizing pyrolysis processes.This work aims to utilize both experimental and modelling approaches to perform the analysis on three biomass feedstocks—wood sawdust,bamboo shred and Jatropha Curcas seed cake residue,and to provide insights for the design and operation of pyrolysis processes.For the experimental part,the study investigated the effect of heating rate,final pyrolysis temperature and sample size on pyrolysis using common thermal analysis techniques.For the modelling part,a transient mathematical model that integrates the feedstock characteristic from the experimental study was used to simulate the pyrolysis progress of selected biomass feedstock particles for reactor scenarios.The model composes of several sub-models that describe pyrolysis kinetic and heat flow,particle heat transfer,particle shrinking and reactor operation.With better understanding of the effects of process conditions and feedstock characteristics on pyrolysis through both experimental and modelling studies,this work discusses on the considerations of and interrelation between feedstock size,pyrolysis energy usage,processing time and product quality for the design and operation of pyrolysis processes.

Electrochemical preparation and characterization of gold-polyaniline core-shell nanocomposites on highly oriented pyrolytic graphite

A simple electrochemical method for the in situ preparation of homogeneously dispersed gold-polyaniline core/shell nanocomposite particles with controlled size on the highly oriented pyrolytic graphite(HOPG)was demonstrated.The HOPG surface was modified preferentially by covalent bonding of a two-dimensional 4-aminophenyl monolayer employing diazonium chemistry.AuCl4 -ions were attached to the Ar-NH2 termination and reduced electrochemically.This results in the formation of Au nuclei that could be further grown into gold nanoparticles.The formation of polyaniline as the shell wrap of Au nanoparticle was established by localized electro-polymerization.These core-shell nanocomposites prepared were characterized by AFM and cyclic voltammetry.The results show that the gold-polyaniline core-shell composites on HOPG have a mean particle size of 100 nm in diameter and the polyaniline shell thickness is about 15 nm.

Effect of wastewater treatment processes on the pyrolysis properties of the pyrolysis tars from sewage sludges

The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, those from the activated sludge process and the indigested sludge from the continuous SBR process respectively, were studied by thermal gravimetric analysis at a heating rate of 10 ℃/min in the nitrogen atmosphere. The results show that the pyrolysis processes of the pyrolysis tars of 1#, 2#, 3# and 5# all can be divided into four stages: the stages of light organic compounds releasing, heavy polar organic compounds decomposition, heavy organic compounds decomposition and the residual organic compounds decomposition. However, the process of 4# pyrolysis tar is only divided into three stages: the stages of light organic compounds releasing, decomposition of heavy polar organic compounds and the residual heavy organic compounds respectively. Both the sludge anaerobic digestion and the "anaerobic" process in wastewater treatment processes make the content of light organic compounds in tars decrease, but make that of heavy organic compounds with complex structure increase. Besides, both make the pyrolysis properties of the tars become worse. The pyrolysis reaction mechanisms of the five pyrolysis tars have been studied with Coats-Redfern equation. It shows that there are the same mechanism functions in the first stage for the five tars and in the second and third stage for the tars of 1#, 2#, 3# and 5#, which is different with the function in the second stage for 4# tar. The five tars are easy to volatile.

Improved water-splitting performances of CuW_(1-x)Mo_xO_4 photoanodes synthesized by spray pyrolysis

CuW（1-x）MoxO4 solid solution of CuWO4 and CuMoO4, which is a copper-based multi-component oxide semiconductor, possesses much narrower band gap than CuWO4. In theory, it can absorb a larger part of the visible spectrum, widening the use of solar spectroscopy and obtaining a higher photo-to-chemical conversion efficiency. In this study, CuW（1-x）MoxO4 thin-film photoanodes on conducting glass were prepared using a simple and low-cost spray pyrolysis method. The resulting CuW（1-x）MoxO4 photoanodes perform higher photocurrent than CuWO4 photoanodes under AM 1.5 G simulated sunlight illumination（100 m W cm^（-2））in 0.1 mol L^（-1） phosphate buffer at pH 7. Combined with IPCE and Mott-Schottky analysis, the enhancement of the photocurrent is due to the improvement of photon utilization and the increase of carrier concentration with the incorporation of Mo atoms. Moreover, with the optimal Mo/W atomic ratio,the photocurrent density increases obviously from 0.07 to 0.46 m A cm^（-2） at 1.23 V（RHE） bias. In addition, compared with particle-assembled thin-film photoanodes prepared by solidphase reaction and drop-necking treatment, the photoanodes prepared by spray pyrolysis have obvious advantages in terms of reducing resistance and facilitating charge transport.