Joseph A. Heppert

Bio: Joseph A. Heppert is an academic researcher from University of Kansas. The author has contributed to research in topics: Ligand & Triple bond. The author has an hindex of 20, co-authored 63 publications receiving 1240 citations. Previous affiliations of Joseph A. Heppert include Indiana University.

Calcium carbonate catalyzed alcoholysis of fats and oils

Abstract: Several alcoholysis catalysts, known to be effective for reactions between simple alcohols and soybean oil, were evaluated and found to be ineffective toward alcoholysis of ethylene glycol with soybean oil under traditional reaction conditions An initial survey of alternative catalysts revealed that organometallic tin complexes were effective but unsatisfactory due to toxicity and difficulty in recovering the catalyst Satisfactory performance for several alcoholysis reactions was achieved with calcium carbonate catalysts even though at higher temperatures, typically greater than 200°C Higher reaction temperatures are not considered to be a problem for flow reactors where heat exchangers can be readily used to minimize energy costs Free fatty acids were esterified by the calcium carbonate and did not appear to inhibit the catalyst Reaction times of 18 min provided essentially complete conversion No decrease in the activity of calcium carbonate was observed after weeks of utilization The robust structure is suitable for use in packed-bed reactors The catalyst used for the flow reactors was pulverized limestone Limestone from two locations was tested and found to be effective Catalyst removal requires only a screening process at the reactor discharge

The metathesis-facilitated synthesis of terminal ruthenium carbide complexes: a unique carbon atom transfer reaction.

Abstract: Ruthenium benzylidene metathesis catalysts react with 2,3-dicarbomethoxymethylene−cyclopropane, eliminating styrene and dimethyl fumarate, and producing the first terminal ruthenium carbide complexes. The products are diamagnetic, air-stable, and moderately soluble in hydrocarbon solvents. An X-ray study of Ru(⋮C:)Cl2(P(C6H11)3) (1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) shows a Ru−C distance of 1.650(2) A, consistent with the presence of a very short Ru−C triple bond.

The Effects of Research & Development Funding on Scientific Productivity: Academic Chemistry, 1990-2009

Abstract: This article examines the relationship between Research & Development (R&D) funding and the production of knowledge by academic chemists Using articles published, either raw counts or adjusted for quality, we find a strong, positive causal effect of funding on knowledge production This effect is similar across subsets of universities, suggesting a relatively efficient allocation of R&D funds Finally, we document a rapid acceleration in the rate at which chemical knowledge was produced in the late 1990s and early 2000s relative to the financial and human resources devoted to its production

Sustainable Conversion of Carbon Dioxide: An Integrated Review of Catalysis and Life Cycle Assessment

Abstract: CO2 conversion covers a wide range of possible application areas from fuels to bulk and commodity chemicals and even to specialty products with biological activity such as pharmaceuticals. In the present review, we discuss selected examples in these areas in a combined analysis of the state-of-the-art of synthetic methodologies and processes with their life cycle assessment. Thereby, we attempted to assess the potential to reduce the environmental footprint in these application fields relative to the current petrochemical value chain. This analysis and discussion differs significantly from a viewpoint on CO2 utilization as a measure for global CO2 mitigation. Whereas the latter focuses on reducing the end-of-pipe problem “CO2 emissions” from todays’ industries, the approach taken here tries to identify opportunities by exploiting a novel feedstock that avoids the utilization of fossil resource in transition toward more sustainable future production. Thus, the motivation to develop CO2-based chemistry does...