Mitigating crosslinking reactions through preconversion strategies. Final report

Technical Report · Fri Jul 01 00:00:00 EDT 1994

DOI:https://doi.org/10.2172/119893· OSTI ID:119893

McMillen, D F; Malhotra, R

The primary objective of this project was to determine the effect of reductive pretreatments of low-rank coals through the use of electron-transfer agents. This potential was explored in laboratory studies through determination of the impact on the evolution of oxygen functions, crosslinking, and conversion. The pretreatments explored include treatment with CO/water/base and hydroquinones or other electron-transfer agents in various combinations. The effects of these pretreatments on functional group distribution, macromolecular structure, and liquefaction were compared with those of pretreatments that have in the past shown promise for improved conversions, such as simple hydrothermal pretreatment, mild hydrogenation with dispersed catalysts, and demineralization. Additional objectives were to improve test procedures for assessing the effect of the pretreatment on subsequent liquefaction and to achieve some understanding of the chemical origins of the effects observed. These tests are: (1) proton magnetic resonance thermal analysis, (PMRTA) for determining the effect of pretreatment on fluidity as liquefaction conditions (temperature, pressure) are approached and (2) a thermogravimetric assay (TGA)-based simulated distillation for convenient measurement of product volatility following small-scale batch-liquefaction experiments. The purpose of the PMRTA test is to gain additional insight into whether beneficial pretreatments primarily affect pre-existing crosslinks in the coals or primarily limit additional crosslinking during liquefaction. The TGA-based simulated distillation test is being developed so that the authors can obtain conversion data and also assess the nature of the product (distillation profile) instead of only a single-point measure of conversion such as wt% conversion to THF-solubles or the yield of 975 F-distillates.

• Research Organization: SRI International, Menlo Park, CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC22-91PC91044
• OSTI ID: 119893
• Report Number(s): DOE/PC/91044-T6; ON: DE96002017; TRN: AHC29527%%35
• Resource Relation: Other Information: PBD: Jul 1994
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL LIQUEFACTION
CHEMICAL REACTION KINETICS
COAL LIQUIDS
CROSS-LINKING
PROGRESS REPORT
MITIGATION
ELECTRON TRANSFER
OPTIMIZATION
THERMAL GRAVIMETRIC ANALYSIS
NUCLEAR MAGNETIC RESONANCE
LIGNITE
SUBBITUMINOUS COAL
HYDROLYSIS
CARBON MONOXIDE
PROMOTERS
STRUCTURAL CHEMICAL ANALYSIS
EXPERIMENTAL DATA