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Title: Coal liquefaction studies using phosphoric acid at moderate temperatures and pressures

Abstract

Concentrated phosphoric acid solutions (65-100% H/sub 3/PO/sub 4/) were studied as a potential homogenous catalytic medium for coal liquefaction at temperatures of up 250/sup 0/C and hydrogen pressures up to 600 psig. Possible catalytic additives, both organic and inorganic, were investigated. Sulfuric acid and molten phosphate and sulfate salt systems were also briefly studied. Sodium pyrophosphate was found to be a beneficial additive to phosphoric acid, in that it reduces the tendency toward foaming upon contacting coal with hot acid, and was used in all subsequent experiments. The materials were relatively ineffective in liquefying coals, except with certain organic additives. Approximately 30% of the sulfur in coal is removed by phosphoric acid treatment, while no effect on nitrogen content is evidenced. Some deashing occurs, with AlCa components most affected. Phosphorus is chemically incorporated into the product coal at levels of 2% or less with most of the incorporated P ending up in the pyridine extract. B.E.T. surface area and scanning electron microscope studies indicate that increased extraction yields of product coals are due more to chemical effects than simply to exposure of more surface area to the extraction solvent used.

Authors:
;
Publication Date:
Research Org.:
California Univ., Berkeley (USA). Lawrence Berkeley Lab.
OSTI Identifier:
5152959
Report Number(s):
LBL-6858
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; COAL LIQUEFACTION; BENCH-SCALE EXPERIMENTS; CHEMISTRY; MOLTEN SALTS; PHASE DIAGRAMS; PHOSPHORIC ACID; SULFURIC ACID; DIAGRAMS; HYDROGEN COMPOUNDS; INORGANIC ACIDS; LIQUEFACTION; SALTS; 010405* - Coal, Lignite, & Peat- Hydrogenation & Liquefaction

Citation Formats

McLean, J.B., and Vermeulen, T. Coal liquefaction studies using phosphoric acid at moderate temperatures and pressures. United States: N. p., 1977. Web. doi:10.2172/5152959.
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McLean, J.B., & Vermeulen, T. Coal liquefaction studies using phosphoric acid at moderate temperatures and pressures. United States. doi:10.2172/5152959.
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McLean, J.B., and Vermeulen, T. Thu . "Coal liquefaction studies using phosphoric acid at moderate temperatures and pressures". United States. doi:10.2172/5152959. https://www.osti.gov/servlets/purl/5152959.
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@article{osti_5152959,
title = {Coal liquefaction studies using phosphoric acid at moderate temperatures and pressures},
author = {McLean, J.B. and Vermeulen, T.},
abstractNote = {Concentrated phosphoric acid solutions (65-100% H/sub 3/PO/sub 4/) were studied as a potential homogenous catalytic medium for coal liquefaction at temperatures of up 250/sup 0/C and hydrogen pressures up to 600 psig. Possible catalytic additives, both organic and inorganic, were investigated. Sulfuric acid and molten phosphate and sulfate salt systems were also briefly studied. Sodium pyrophosphate was found to be a beneficial additive to phosphoric acid, in that it reduces the tendency toward foaming upon contacting coal with hot acid, and was used in all subsequent experiments. The materials were relatively ineffective in liquefying coals, except with certain organic additives. Approximately 30% of the sulfur in coal is removed by phosphoric acid treatment, while no effect on nitrogen content is evidenced. Some deashing occurs, with AlCa components most affected. Phosphorus is chemically incorporated into the product coal at levels of 2% or less with most of the incorporated P ending up in the pyridine extract. B.E.T. surface area and scanning electron microscope studies indicate that increased extraction yields of product coals are due more to chemical effects than simply to exposure of more surface area to the extraction solvent used.},
doi = {10.2172/5152959},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 1977},
month = {Thu Dec 01 00:00:00 EST 1977}
}
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Technical Report:
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DOI:  10.2172/5152959
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