ISSN:0278-4491    

DOI:10.1002/ep.670170402

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670170403

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670170405

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670170407

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670170408

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670170409

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670170410

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

摘要:

AbstractDigested sewage sludge and other biomass such as wood saw‐dust can be mixed with a corn starch gel to form a viscous paste. This paste can be delivered to a supercritical flow reactor by means of a cement pump. Different types of feedstocks are used in this work: sewage sludge (up to 7.69 wt%) mixed in the corn starch paste, poplar wood sawdust (up to 11.46 wt%) mixed in the corn starch paste. When rapidly heated in a flow reactor at pressures above the critical pressure of water (22 MPa) the paste vaporizes. A packed bed of carbon catalyst in the reactor operating at 650°C causes the tarry vapors to react with water, producing hydrogen, carbon dioxide, and some methane with a trace of carbon monoxide. Thus we describe a practical method for the total, supercritical steam reforming of biomass to produce hydrogen at high pressure. The steam reforming process produces effectively no tar. Its only products are a hydrogen rich gas, and a clean water, which can be recycl

ISSN:0278-4491    

DOI:10.1002/ep.670170411

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

摘要:

AbstractSoftware for the computer generation of kinetic models was exploited to construct a mechanistic kinetic model for alcohol oxidation in high temperature (300 ≤T/°C≤380) water. The complexities of the oxidation mechanism were captured by a detailed mechanism consisting of eight reaction families. These included hydrogen abstraction by oxygen, hydrogen abstraction by radical, β‐scission, non‐terminating radical reactions, isomerizations, decomposition, molecular addition and termination steps. The mechanistic model was generated computationally, using the graph theory notions where the molecules and radicals are represented as atomic connectivity matrices and the reactions as matrix operators. The free‐radical kinetics of C1‐C4 alcohols exhibited features of both gas‐phase combustion and liquid‐phase oxidation chemistry. The imposition of Evans‐Polanyi relationships for the associated rate constants provided a significant reduction in model parameters with little loss of predictive capability. Kinetic parameter vectors, one for each reaction family, obtained by optimizing the model predictions to pure‐component ethanol data provided a very good fit to pure component kinetics of other alcohols, as wel

ISSN:0278-4491    

DOI:10.1002/ep.670170412

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY

摘要:

AbstractSupercritical water oxidation (SCWO) is a promising technology for the incineration of hazardous compounds in aqueous solutions. Even though the entire oxidation process in carbon dioxide is still somewhat unknown, this would be the optimum way of completely oxidizing the hazardous compounds which are first extracted by supercritical carbon dioxide. Results of high‐pressure oxidation of model compounds (ethanol, methanol, toluene) in carbon dioxide compared to SCWO are reported. Such comparisons will help to clarify the role of the reaction medium in high‐pressure oxidation.Under optimum conditions, oxidation in CO2leads to the same excellent TOC conversion of more than 99.9% as in H2O for methanol and ethanol, and of more than 98% for toluene. Under certain conditions, a reaction mixture containing carbon dioxide ignites at a lower temperature than the comparable reaction mixture with wa

ISSN:0278-4491    

DOI:10.1002/ep.670170413

出版商:American Institute of Chemical Engineers    

年代:1998

数据来源: WILEY