Papers by Mark Holtzapple
Encyclopedia of Food Sciences and Nutrition, 2003
Encyclopedia of Food Sciences and Nutrition, 2003
Biomass & Bioenergy, Mar 1, 2017
Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles, Apr 18, 2013
Cet article fait partie du dossier thématique ci-dessous publié dans la revue OGST, Vol. 68, n°5,... more Cet article fait partie du dossier thématique ci-dessous publié dans la revue OGST, Vol. 68, n°5, pp. 789-946 et téléchargeable ici D o s s i e r DOSSIER Edited by/Sous la direction de : A. Daudin et A. Quignard PART 2 Second and Third Generation Biofuels: Towards Sustainability and Competitiveness Deuxième et troisième génération de biocarburants : développement durable et compétitivité
Science of The Total Environment, 2019
Waste biomass includes municipal solid waste (MSW), municipal sewage sludge (SS), industrial bios... more Waste biomass includes municipal solid waste (MSW), municipal sewage sludge (SS), industrial biosludge, manure, and agricultural residues. When treated with lime, biomass is highly digestible by a mixed culture of acid-forming microorganisms. Lime treatment doubles the ruminant digestibility of agricultural residues; thus, it may be used to upgrade their feed value. Alternatively, lime-treated biomass can be fed to an industrial-scale mixed-acid fermentation where acetic, propionic, and butyric acids are produced. To control the pH, these acids are neutralized with calcium carbonate. The resulting calcium salts can be used to reduce sulfur emissions from industrial furnaces by directly spraying salt solutions into the combustor. Alternatively, the calcium salts may be thermally converted to ketones - such as acetone, methyl ethyl ketone, and diethyl ketone - which are useful industrial solvents. Further, these ketones may be hydrogenated to alcohols - such as propanol, butanol, and pentanol - which may be used as industrial solvents or motor fuel. Alternatively, the calcium salts may be acidified to recover the acids. In recognition of the potential environmental benefits of this technology, it bas been awarded the 1996 Presidential Green Chemistry Challenge Award.
CABI eBooks, 2005
Abstract This chapter first describes a new lignocellulosic process for the conversion of biomass... more Abstract This chapter first describes a new lignocellulosic process for the conversion of biomass into ethanol. A simulation model is then used to determine the feasibility of a 30-million-gal/year lignocellulosic ethanol plant in Texas, USA, in comparison to a similar-...
CRC Press eBooks, Jan 19, 2006
Separation and Purification Technology, Jun 1, 2021
Biomass & Bioenergy, Oct 1, 2017
Abstract Sludge is the solids recovered from wastewater treatment. Its high content of organic ma... more Abstract Sludge is the solids recovered from wastewater treatment. Its high content of organic matter makes it a potential biomass resource for renewable energy production. In this study, batch and continuous countercurrent fermentations were performed with a 60:40 mixture (dry weight basis) of lime-treated bagasse:sludge. This combination provides an optimal C/N ratio and therefore enhances yield. Two trains of continuous fermentations were performed using different volatile solids loading rates (VSLR) and liquid retention times (LRT). The highest total carboxylic acids concentration obtained was 60.8 g L −1 with a total acid yield of 420 g kg −1 of VS added and an acid productivity of 2.31 g L −1 d −1 . In studies on co-fermentation of lignocellulosic biomass, this acid concentration is the highest reported in MixAlco™ (a patented process that converts biomass to a mixture of alcohols). This study shows that wastewater sludge is a valuable resource for liquid transportation fuels, and provides an attractive replacement for fossil fuels.
Renewable Energy, Apr 1, 2020
International Chain Elongation Conference, Nov 2, 2020
Contribution to the International Chain Elongation Conference 2020 | ICEC 2020.
Desalination, Mar 1, 2023
Biomass & Bioenergy, Oct 1, 2013
The MixAlco™ process ferments lignocellulosic biomass to carboxylate salts that are thermally dec... more The MixAlco™ process ferments lignocellulosic biomass to carboxylate salts that are thermally decomposed into ketones, which are then chemically converted to a wide variety of chemicals and fuels. To perform these decompositions, suitable reaction models are necessary to properly design, scale, and optimize commercial reactors. For three salt types (calcium acetate, and two types of mixed calcium carboxylate salts), activation energy was determined using three isoconversional methods that employed TGA curves at different heating rates. For all three salt types, activation energy varied significantly with conversion. The average activation energy for calcium acetate was 556.75 kJ mol−1, and the activation energies for the two mixed calcium carboxylate salts were 232.87, and 176.55 kJ mol−1. In addition, three functions of conversion were employed to see which one best modeled the experimental data. The Sestak–Berggren model provides the best universal fit for all three salt types.
Ashrae Transactions, 1989
... Titre du document / Document title. Reducing energy costs in vapor-compression refrigeration ... more ... Titre du document / Document title. Reducing energy costs in vapor-compression refrigeration and air conditioning using liquid recycle. I: Comparison of ammonia and R-12. Auteur(s) / Author(s). HOLTZAPPLE MT (1) ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). ...
Biomass & Bioenergy, Jul 1, 2019
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Papers by Mark Holtzapple