Sikander H. Hakim

Increasing the revenue from lignocellulosic biomass: Maximizing feedstock utilization

Replacing petroleum by biomass can be economically feasible by generating revenue from the three primary biomass constituents. The production of renewable chemicals and biofuels must be cost- and performance- competitive with petroleum-derived equivalents to be widely accepted by markets and society. We propose a biomass conversion strategy that maximizes the conversion of lignocellulosic biomass (up to 80% of the biomass to useful products) into high-value products that can be commercialized, providing the opportunity for successful translation to an economically viable commercial process. Our fractionation method preserves the value of all three primary components: (i) cellulose, which is converted into dissolving pulp for fibers and chemicals production; (ii) hemicellulose, which is converted into furfural (a building block chemical); and (iii) lignin, which is converted into carbon products (carbon foam, fibers, or battery anodes), together producing revenues of more than

A highly selective route to linear alpha olefins from biomass-derived lactones and unsaturated acids.

500 per dry metric ton of biomass. Once de-risked, our technology can be extended to produce other renewable chemicals and biofuels.

Direct observation of macropore self-formation in hierarchically structured metal oxides

This work demonstrates the use of Lewis-acid catalysts, such as gamma-alumina and tungstated alumina, for selective production of linear alpha olefins by decarboxylation of lactones and unsaturated carboxylic acids.

Synthesis of Supported RhMo and PtMo Bimetallic Catalysts by Controlled Surface Reactions

The current work presents an unprecedented direct observation of macropore formation in the spontaneous self-assembly process to obtain hierarchical meso/macroporous metal oxides made possible with the help of an unusual titanium alkoxide.

A Solvent‐Free Synthesis of Lignin‐Derived Renewable Carbon with Tunable Porosity for Supercapacitor Electrodes

We previously described a synthesis method to prepare bimetallic catalysts with narrow nanoparticle size and composition distributions by means of controlled surface reactions (CSR) between a reduced supported metal nanoparticle and an organometallic precursor of an oxophilic promoter metal. Herein, we report a comparison of such catalysts with those prepared by traditional incipient wetness impregnation. STEM/EDS analysis indicates that catalysts prepared by CSR exhibit more effective interaction of metals, thereby minimizing the undesirable formation of component‐rich nanoparticles and/or monometallic domains. Reaction kinetics studies using these bimetallic catalysts reveal that optimal conversion rates in a selective CO hydrogenolysis reaction (i.e., hydrogenolysis of 2‐(hydroxymethyl)tetrahydropyran to 1,6‐hexanediol) could be achieved using a lower amount of the oxophilic promoter metal for the catalysts prepared by the CSR approach, as compared to their impregnated counterparts.

Corrections to “PtMo Bimetallic Catalysts Synthesized by Controlled Surface Reactions for Water Gas Shift”

Synthesis of multiphase materials from lignin, a biorefinery coproduct, offers limited success owing to the inherent difficulty in controlling dispersion of these renewable hyperbranched macromolecules in the product or its intermediates. Effective use of the chemically reactive functionalities in lignin, however, enables tuning morphologies of the materials. Here, we bind lignin oligomers with a rubbery macromolecule followed by thermal crosslinking to form a carbon precursor with phase contrasted morphology at submicron scale. The solvent-free mixing is conducted in a high-shear melt mixer. With this, the carbon precursor is further modified with potassium hydroxide for a single-step carbonization to yield activated carbon with tunable pore structure. A typical precursor with 90 % lignin yields porous carbon with 2120 m2  g-1 surface area and supercapacitor with 215 F g-1 capacitance. The results show a simple route towards manufacturing carbon-based energy-storage materials, eliminating the need for conventional template synthesis.

A comparative study of macroporous metal oxides synthesized via a unified approach

Surface Reactions for Water Gas Shift” Canan Sener,†,# Thejas S. Wesley,† Ana C. Alba-Rubio,† Mrunmayi D. Kumbhalkar,† Sikander H. Hakim,† Fabio H. Ribeiro,‡ Jeffrey T. Miller, and James A. Dumesic*,†,# †Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, United States ‡School of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, Indiana 47907-2100, United States Chemical Sciences and Energy Division, Argonne National Laboratory, 9700 S. Cass Avenue, Building 200, Argonne, Illinois 60439-4837, United States DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin 53726, United States