Industry University Cooperative Research on High Yield Syntheses of Activated Carbons

摘要：一种通过高压操作从生物质中制造木炭的新方法使工业上通常实现的木炭产量翻了一番，并且能够在仅一小时的反应时间后将原木转化为木炭。这项研究旨在利用这一新知识将生物质原料活性炭的通常工业产量提高三倍。合成高收率（HY）活性炭的技术障碍包括：(1)HY活性炭在氧气和蒸汽作用下的气化速率规律是什么？(2)这些速率定律是否可以包含在Thiele模量分析中，以确定产生具有高表面积或其他理想性能的活性炭的条件？(3)能否在低温下合成活性炭？(4)浸渍剂可以用来合成具有特别理想性能的有价值的碳吗？(5)什么反应条件能使所需碳的产率最大化？为了克服上述障碍，这项工作将集中于下列目标：(i)从原料和预处理的生物质原料生产各种HY炭。确定这些HY炭在氧和水作用下气化的速率规律。（ii）利用Thiele模量分析确定活化的有利条件。（iv）在中高温和高压条件下，在蒸汽（或超临界水）中的氧气（空气）和在很大压力范围内的蒸汽（或超临界水）活化NY炭；(v)确定HY活性炭的化学、物理和吸附性能。（vi）在综合上述结果的基础上，确定产生产率为20%或更高的理想活性炭的条件和预处理。两个实验测试平台将用于测量动力学和激活木炭：一个大型，加压，填料床反应器结合高压蒸汽发生器，两者的设计都满足ASME cod要求，和一个小直径，填料床，超临界流反应器。匈牙利科学院的合作者还将通过热重分析测量低压下HY木炭的气化速率。这项工作代表了夏威夷大学、两家关注回收和生物质利用的公司以及活性炭的商业来源之间的伙伴关系。这些与私营工业的联系将确保这项研究产生的新知识的迅速传播和使用。

Abstract - Antal - 9521423 A new method for manufacturing charcoal from biomass by operating at elevated pressures doubles the yield of charcoal ordinarily realized by industry, and is able to convert wood logs to charcoal after only one hour of reaction time. This research is aimed at employing this new knowledge to triple the usual industrial yields of activated carbons from biomass feedstocks. Technical barriers to the synthesis of high yield (HY) activated carbons include: (1) What rate laws describe the gasification of HY charcoal by oxygen and steam? (2) Can these rate laws be included in a Thiele modulus analysis to define conditions which produce activated carbons with high surface areas or other desirable properties? (3) Can activated carbons be synthesized at low temperatures? (4) Can impregnants be used to synthesize valuable carbons with peculiarly desirable properties? (5) What reaction conditions maximize the yields of desirable carbons? To overcome the above barriers, this work will focus on the following objectives: (i) Produce various HY charcoals from raw and pretreated biomass feedstocks. (ii) Determine the rate laws governing gasification of these HY charcoals by oxygen and water. (ii) Use Thiele modulus analysis to identify favorable conditions for activation. (iv) Activate the NY charcoals by oxygen (air) in steam (or supercritical water) at moderate to high temperatures and elevated pressures, and by steam (or supercritical water) at moderate to high temperatures over a very large range in pressures, (v) Determine the chemical, physical, and adsorptive properties of the HY activated carbons. (vi) Based on a synthesis of the foregoing results, identify conditions and pretreatments which produce desirable activated carbons with yields of 20% or more. Two experimental testbeds will be used to measure kinetics and activate the charcoals: a large, pressurized, packed bed reactor combined with a high pressure steam generator, both designed to satisfy ASME cod e requirements, and a small diameter, packed bed, supercritical flow reactor. Collaborators with the Hungarian Academy of Sciences will also measure HY charcoal gasifications rates at low pressures by thermogravimetric analysis. This work represents a partnership between the University of Hawaii, two companies concerned with recycling and biomass utilization, and a commercial source of activated carbons. These linkages to private industry will ensure the rapid dissemination and employment of new knowledge generated by this research.