Membranes for CO2 capture - report on pilot plant tests

Although the main part of the world has now accepted the fact that the global climate change is due to human activities, we will not be able to switch gear and only go for “green energy” without fossil fuels for still many decades. One way of contributing to combat the climate change is hence to capture the CO2 from fossil fuel flue gases, and either find ways to utilize the CO2 or sequestrate it in aquifers or depleted oil fields, while we slowly develop a “green way of living”. Membranes will for sure represent one of the emerging technologies to be used for CO2 capture. Today there are a few pilot installations around the world using different types of membranes, to demonstrate and learn the best way of optimize such a capture plant – in Norway there are two of such kind; one at a cement factory in Brevik in South Norway and one at a test center at Tiller in Trondheim. At the cement plant the CO2 concentration in the flue gas can be close to 20 vol%, while at the Tiller plant there is a possibility to vary the CO2 concentration over a range of 8 – 12vol%. At the cement plant the flue gas contains quite a few unwanted components, while at Tiller the flue gas is relatively “clean”. The type of membrane installed at these two sites is hollow fiber modules where the support fiber is polysulfone (PSf) and the coated mebrane is a polyvinylamine (PVAm). The technique for applying the coating is not straight forward, and an efficient flue gas separation depends strongly on a successful coating procedure. Going from lab tests using a few cm2 up to several m2 of a commercial scale module is extremely challenging. The tests are being performed with 2 or 3 modules in parallel or series, but not yet as a complete two-stage process. Based on obtained results, a full scale process will be simulated. Preliminary results using only one stage at Tiller are already documenting an encouraging 58% CO2 in permeate from 7% CO2 in feed line. The PVAm membrane is based on facilitated transport of the CO2 through the membrane, which means that water needs to be handled in the separation process – this has again a large influence on the engineering design of the process and process operation parameters. The presentation will highlight and report some results and challenges from these two tests sites. Acknowledgement The GASSNOVA projects 229949 and 249036 are highly recognized for contributions from the CLIMIT-Demo program in the Norwegian Research Council, Air Products and Chemicals, Inc. (USA), Air Products AS (Norway), Alberta Funders (Canada), Statoil ASA, NORCEM (Heidelberg Cement), SINTEF Materials and Chemistry, DNV GL (The Netherlands)

Structure–property relationships of iron arsenide superconductors

Iron based superconductors sent material scientists into a renewed excitement reminiscent of the time when the first high-Tc superconductors were discovered 25 years ago. This feature article reviews relationships between structural chemistry and magnetic as well as superconducting properties of iron arsenide compounds, which are outstandingly rich and uniquely coupled. Particular attention is paid to the nature of the structural phase transitions of the parent compounds and their possible origins, on effects of doping on the crystal structures and on the coexistence of magnetic ordering and superconductivity. In spite of the many fascinating insights that have already enriched the research on superconductivity, many questions are still open and prove iron based superconductors to be a good recipe for future discoveries in this lively field

The Role of Adiposity in Cardiometabolic Traits: A Mendelian Randomization Analysis

Peer reviewe

Author Correction:Study of 300,486 individuals identifies 148 independent genetic loci influencing general cognitive function

Christina M. Lill, who contributed to analysis of data, was inadvertently omitted from the author list in the originally published version of this article. This has now been corrected in both the PDF and HTML versions of the article

High-Flux Carbon Molecular Sieve Membranes for Gas Separation

Carbon membranes have great potential for highly selective and cost-efficient gas separation. Carbon is chemically stable and it is relative cheap. The controlled carbonization of a polymer coating on a porous ceramic support provides a 3D carbon material with molecular sieving permeation performance. The carbonization of the polymer blend gives turbostratic carbon domains of randomly stacked together sp(2) hybridized carbon sheets as well as sp(3) hybridized amorphous carbon. In the evaluation of the carbon molecular sieve membrane, hydrogen could be separated from propane with a selectivity of 10000 with a hydrogen permeance of 5 m(3)(STP)/(m(2)hbar). Furthermore, by a post-synthesis oxidative treatment, the permeation fluxes are increased by widening the pores, and the molecular sieve carbon membrane is transformed from a molecular sieve carbon into a selective surface flow carbon membrane with adsorption controlled performance and becomes selective for carbon dioxide