Electrocatalytic conversion technology of biomass-derived oxygenates to produce renewable fuels and chemicals

김형주,( George W. Huber ) 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

Proton exchange membrane (PEM) fuel cells have been developed in the last 20 years to be highly efficient methods to produce electricity from oxygenated compounded. Recently, the PEM technology has been used to produce a wide range of products from the electrocatalytic oxidation and reduction of biomass-derived molecules. The electrocatalytic oxidation and reduction of biomass-derived oxygenates has several key advantages over other methods of biomass conversion. The most significant advantage is that no oxygen gas (or hydrogen gas) is required for the reactions. Another advantage is that this technology stores electricity as a liquid transportation fuel that fits into existing infrastructure. All the reactions in the PEM technology take place in one simple reactor that could easily be scaled up to a commercial level. Finally, one of the most important advantages of electrocatalysis compared to conventional catalysis is the ability to manipulate the size of the activation barrier, and thus reaction selectivity, by controlling the electrode potential. Therefore, reactions that require high temperatures and pressures in a conventional catalytic system will readily occur at atmospheric temperatures and pressures in the electrocatalytic PEM reactor due to the application of a voltage. In this presentation we will demonstrate how PEM technology can be used to produce different fuels and chemicals from biomass-derived oxygenates.

Enhanced oxygen reduction performance over Pt/C-dispersed nanowire network catalysts

김형주,서민호,최승목,임은자,조정모,( George W. Huber ),김원배 한국공업화학회 2010 한국공업화학회 연구논문 초록집 Vol.2010 No.-

Aqueous-phase hydrodeoxygenation of sorbitol over bifunctional catalysts

김용태,( James A. Dumesic ),( George W. Huber ) 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.1

Hydrodeoxygenation (HDO) is a platform technology for conversion of biomass feedstocks into a range of fuels and chemicals including C1-C6 alkanes, C1-C6 mono-alcohols, C2-C6 polyols, and larger intermediate. The combination of metal and acid sites on the bifunctional catalytic system is important to tune the ratio of C-O bond to C-C bond cleavage during HDO reactions. The challenge with HDO is to selectively produce targeted products that can be used as fuel blendstocks and chemicals tuned by chemistry and reaction engineering. Understanding the reaction networks in HDO has aided in the design of efficient bifunctional catalysts. In this presentation we will discuss the differences between two fundamentally different classes of bifunctional metal-acid catalysts and show how we can modify HDO reaction.

Selective glycerol oxidation by electrocatalytic dehydrogenation

김형주,김철웅,정순용,( George W. Huber ),김원배 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

In this work, we present a simple and direct conversion of glycerol into glyceric acid by anodic oxidation in two different types of electrocatalytic reactors without using stoichiometric chemical oxidants such as oxygen. The two reactor types include 1) an electrocatalytic batch reactor with a three-electrode system with catalyst-coated carbon paper as the working electrode and 2) a continuous flow electrocatalytic reactor based on PEM technology. We also performed non-electrocatalytic glycerol oxidation using a conventional catalytic batch reactor to compare conventional catalytic performances with electrocatalytic reactors. High yield of glyceric acid (79.9% yield at 91.8% conversion) was achieved from the electrocatalytic batch reactor using a carbon supported Pt catalyst (Pt/C). A high selectivity of glyceric acid (> 80% selectivity) was also observed in the continuous flow electrocatalytic reactor. The turnover frequency (TOF) for the glycerol conversion was about 10 times higher in the continuous flow electrocatalytic reactor than in the conventional catalytic batch system.

1-부텐 저온 올리고머화 반응을 통한 장쇄 올레핀의 합성반응

김용태,( Joseph P. Chada ),( Zhuoran Xu ),( Yomaira J. Pagan-torres ),( Devon C. Rosenfeld ),( William L. Winniford ),( Eric Schmidt ),( George W. Huber ),전기원 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0

현재 북미지역은 셰일가스의 수압파쇄법의 발달로 인하여 풍부한 천연가스자원을 확보하고 있다. 셰일가스는 C1-C4 범위의 알칸을 함유하고 있으며 이는 다양한 화학산업에 원료로 사용될 수 있다. 올레핀(C2-C4)은 즉시 이용가능하고, 가격경제적이며, 쉽게 화학물질로 전환가능하여 화학산업에서 주요 building block으로 쓰이고 있다. 장쇄 올레핀은 산촉매를 사용한 C2-C4범위의 올레핀의 올리고머화 공정을 통하여 합성될 수 있다. 장쇄 올레핀 (C6-C30)은 폴리에틸렌 (40%), 알코올 (17%), 폴리알파올레핀 (12%), 플라스틱 (7%), 오일 (6%) 등에 사용할 수있다. 본 연구에서는, 제올라이트 (H-ferrierite)를 사용하여 1-부텐 올리고머화 반응을 진행하였다. Two-dimensional gas chromatography (GCxGC-FID-MS)를 사용하여 200개 이상의 이성질체를 포함한 파라핀, 올레핀, 아로마틱, 나프텐, 나프탈린을 검출하였다. 표면에 카보양이온 화학적 성질을 갖는 촉매가 반응공정 변수에 따라서 선택적으로 작동할 수 있는지 (1) Mechanism, (2) Kinetic, (3) Stability 측면에서 살펴보았다.

Highly selective transformation of glycerol to dihydroxyacetone without using oxidants by a PtSb/C-catalyzed electrooxidation process

Lee, Seonhwa,Kim, Hyung Ju,Lim, Eun Ja,Kim, Youngmin,Noh, Yuseong,Huber, George W.,Kim, Won Bae The Royal Society of Chemistry 2016 GREEN CHEMISTRY Vol.18 No.9

<P>We demonstrate an electrocatalytic reactor system for the partial oxidation of glycerol in an acidic solution to produce value-added chemicals, such as dihydroxyacetone (DHA), glyceraldehyde (GAD), glyceric acid (GLA), and glycolic acid (GCA). Under optimized conditions, the carbon-supported bimetallic PtSb (PtSb/C) catalyst was identified as a highly active catalyst for the selective oxidation of glycerol in the electrocatalytic reactor. The product selectivity can be strongly controlled as a function of the applied electrode potential and the catalyst surface composition. The main product from the electrocatalytic oxidation of glycerol was DHA, with a yield of 61.4% of DHA at a glycerol conversion of 90.3%, which can be achieved even without using any oxidants over the PtSb/C catalyst at 0.797 V (vs. SHE, standard hydrogen electrode). The electrocatalytic oxidation of biomass-derived glycerol represents a promising method of chemical transformation to produce value-added molecules.</P>

Electrocatalytic reduction of acetone in a proton-exchange-membrane reactor: a model reaction for the electrocatalytic reduction of biomass.

Green, Sara K,Tompsett, Geoffrey A,Kim, Hyung Ju,Bae Kim, Won,Huber, George W Wiley-VCH 2012 CHEM SUS CHEM Vol.5 No.12

<P>Acetone was electrocatalytically reduced to isopropanol in a proton-exchange-membrane (PEM) reactor on an unsupported platinum cathode. Protons needed for the reduction were produced on the unsupported Pt-Ru anode from either hydrogen gas or electrolysis of water. The current efficiency (the ratio of current contributing to the desired chemical reaction to the overall current) and reaction rate for acetone conversion increased with increasing temperature or applied voltage for the electrocatalytic acetone/water system. The reaction rate and current efficiency went through a maximum with respect to acetone concentration. The reaction rate for acetone conversion increased with increasing temperature for the electrocatalytic acetone/hydrogen system. Increasing the applied voltage for the electrocatalytic acetone/hydrogen system decreased the current efficiency due to production of hydrogen gas. Results from this study demonstrate the commercial feasibility of using PEM reactors to electrocatalytically reduce biomass-derived oxygenates into renewable fuels and chemicals.</P>

Production of renewable C4–C6 monoalcohols from waste biomass-derived carbohydrate via aqueous-phase hydrodeoxygenation over Pt-ReO<i> _x </i>/Zr-P

Lee, Jechan,Ro, Insoo,Kim, Hyung Ju,Kim, Yong Tae,Kwon, Eilhann E.,Huber, George W. Elsevier 2018 Process safety and environmental protection Vol.115 No.-

<P><B>Abstract</B></P> <P>A bifunctional catalyst, Pt-ReO<I> <SUB>x</SUB> </I> supported on zirconium phosphate (Pt-ReO<I> <SUB>x</SUB> </I>/Zr-P), was prepared and tested for aqueous-phase hydrodeoxygenation (APHDO) of waste biomass-derived carbohydrate (<I>e.g.</I>, sorbitol) to produce C4–C6 monoalcohols such as butanol, pentanol, and hexanol in a high-pressure continuous flow reactor. For steady-state operation, the reaction parameters were optimized to achieve the highest yield of C4–C6 monoalcohols from APHDO of sorbitol. Approximately 30% yield of C4–C6 monoalcohols was reached at optimal reaction conditions (temperature: 453K, pressure: 6.21MPa, weight hourly space velocity (WHSV): 0.16h<SUP>−1</SUP>) for APHDO of sorbitol over the Pt-ReO<I> <SUB>x</SUB> </I>/Zr-P catalyst. The effect of catalyst support for monoalcohol production was also evaluated by comparison between the Pt-ReO<I> <SUB>x</SUB> </I>/Zr-P and carbon supported Pt-ReO<I> <SUB>x</SUB> </I> (Pt-ReO<I> <SUB>x</SUB> </I>/C) catalysts. The Zr-P supported catalyst exhibited a four times higher yield of C4–C6 monoalcohols than the carbon supported catalyst, suggesting that acid sites atomically separated from metal sites play a crucial role in producing monoalcohols via CO bond cleavage of chemical intermediates produced during APHDO of sorbitol.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Production of C4–C6 monoalcohols from sorbitol via hydrodeoxygenation. </LI> <LI> Pt-ReO<I> <SUB>x</SUB> </I>/Zr-P catalyst gave 30% C4–C6 monoalcohol yield for APHDO of sorbitol. </LI> <LI> Optimized APHDO conditions for C4–C6 monoalcohol production from sorbitol. </LI> </UL> </P>

Plasmon-Enhanced Photoelectrochemical Water Splitting with Size-Controllable Gold Nanodot Arrays

Kim, Hyung Ju,Lee, Sang Ho,Upadhye, Aniruddha A.,Ro, Insoo,Tejedor-Tejedor, M. Isabel,Anderson, Marc A.,Kim, Won Bae,Huber, George W. American Chemical Society 2014 ACS NANO Vol.8 No.10

<P>Size-controllable Au nanodot arrays (50, 63, and 83 nm dot size) with a narrow size distribution (±5%) were prepared by a direct contact printing method on an indium tin oxide (ITO) substrate. Titania was added to the Au nanodots using TiO<SUB>2</SUB> sols of 2–3 nm in size. This created a precisely controlled Au nanodot with 110 nm of TiO<SUB>2</SUB> overcoats. Using these precisely controlled nanodot arrays, the effects of Au nanodot size and TiO<SUB>2</SUB> overcoats were investigated for photoelectrochemical water splitting using a three-electrode system with a fiber-optic visible light source. From UV–vis measurement, the localized surface plasmon resonance (LSPR) peak energy (<I>E</I><SUB>LSPR</SUB>) increased and the LSPR line width (Γ) decreased with decreasing Au nanodot size. The generated plasmonic enhancement for the photoelectrochemical water splitting reaction increased with decreasing Au particle size. The measured plasmonic enhancement for light on/off experiments was 25 times for the 50 nm Au size and 10 times for the 83 nm Au nanodot size. The activity of each catalyst increased by a factor of 6 when TiO<SUB>2</SUB> was added to the Au nanodots for all the samples. The activity of the catalyst was proportional to the quality factor (defined as <I>Q</I> = <I>E</I><SUB>LSPR</SUB>/Γ) of the plasmonic metal nanostructure. The enhanced water splitting performance with the decreased Au nanodot size is probably due to more generated charge carriers (electron/hole pair) by local field enhancement as the quality factor increases.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2014/ancac3.2014.8.issue-10/nn504484u/production/images/medium/nn-2014-04484u_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn504484u'>ACS Electronic Supporting Info</A></P>