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In this paper, the design and control of an improved process for the manufacture of a fuel additive (glycerol tertiary butyl ethers, GTBE) from glycerol and isobutylene is developed. The improved process redirects one recycle stream, uses a stripping column instead of a flash tank to recover isobutylene, and uses a rectifying column instead of a distillation column to purify the product. Economic analysis shows that the improved process has a 22% lower total annual cost (TAC) than the best known process published in the literature. Significant increases in the selectivity of the overall process from 84.7% to 99.3% can also be realized by comparing the optimized improved design versus the original design. Dynamic simulations were also conducted and indicated that stringent product specification can be met with a simple decentralized feedback control structure despite impurities in the feed streams and also changes in the throughput.

Background: Lung cancer is one of the most devastating diseases worldwide, and it is meaningful to assess the subtype and epidermal growth factor receptor (EGFR) status in lung cancer noninvasively by imaging methods. Purpose: To differentiate noninvasively small cell lung cancer (SCLC) from nonsmall cell lung cancer (NSCLC), and EGFR mutation-type from wild-type NSCLC by comparing amide proton transfer-weighted imaging (APTWI), diffusion-weighted imaging (DWI), and 2-[ 18 F]-fluoro-2-deoxy-D-glucose positron emission tomography ( 18 F-FDG PET). Study Type: Prospective. Population: A total of 99 patients with lung cancer. Field Strength/Sequence: APTWI and DWI at 18 F-FDG PET/MRI 3.0 T. Assessment: The apparent diffusion coefficient (ADC), magnetization transfer ratio asymmetry (MTRasym [3.5 ppm]), maximum standardized uptake value (SUV max ), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were calculated and compared. Statistical Tests: Individual sample t-test, Mann-Whitney U test, Logistic regression, and P < 0.05 were considered statistically significant. Results: In NSCLC, MTRasym (3.5 ppm), MTV, and TLG were significantly lower and ADC was significantly higher than in SCLC; MTRasym (3.5 ppm) was significantly higher and SUV max , MTV, and TLG were significantly lower in EGFR mutationtype NSCLC than in EGFR wild-type NSCLC. In the identification of SCLC and NSCLC, MTRasym (3.5 ppm), ADC, and MTV were independent predictors, the AUCs of the combination of independent predictors, MTV, TLG, MTRasym (3.5 ppm), and ADC were 0.942, 0.875, 0.843, 0.814, and 0.687, respectively. In the identification of EGFR mutation-type and wild-type NSCLC, MTRasym (3.5 ppm) and MTV were independent predictors, the AUCs of the combination of independent predictors, TLG, MTV, MTRasym (3.5 ppm), and SUV max were 0.919, 0.834, 0.813, 0.795, and 0.771, respectively.