Anti-NCL monoclonal antibody, clone 475-6

To develop a process for simultaneous extraction and recovery of nitric acid and gold from gold-bearing aqua regia solutions, solvent extraction study was conducted by using tributyl phosphate (TBP) as the extractant. The extraction behaviors of acid from the pure aqua regia, nitric acid, and hydrochloric acid were investigated with varying concentration of extractant, and the concentration ratio of HNO3 and NCl. The simultaneous recovery of HNO3 and Au with the recycling of HCl from the gold-bearing aqua regia solutions was also examined. Selective stripping was then carried out for co-extracted HNO3 and Au. Equilibrium conditions for HNO3 and Au recovery optimized from the experimental results have been found to be: extraction using 80 vol% TBP at O/A ratio of 1, four contacts of stripping for HNO3 at O/A ratio of 1 using distilled water, and two contacts of stripping for Au at an O/A ratio of 1 using a mixed solution at 1:1 (vol.) ratio of 0.1 M sodium thiosulfate (Na2O2S3) and 0.1 M ammonium hydroxide (NH4OH). It was thus possible to simultaneously recover HNO3 and Au from the gold bearing aqua regia solution through co-extraction and selective stripping of HNO3 and Au leaving HCl in the raffinate for recycling.

There have been continuous efforts by researchers and power producing companies to reduce various costs involved in solar power tower (SPT) plants. Economically deploying conventional SPT plants for industries using thermal or thermo-chemical processes which need temperatures >1100 K could be challenging. Here, the overall economics of deployment of conventional SPT could go unfair as such design needs larger heliostat field, therefore costlier stiffer heliostats to reach high concentration ratio (CR). These challenges can be solved by beam-down SPT which uses secondary reflector mounted on tower top and receiver cum secondary concentrator on the ground could achieve desired CR, is one potential candidate to save on tower construction and pumping costs. Using beam-down SPT heat can be made available at the ground which opens an option of extracting the heat using natural circulation loop (NCL). The current paper explores the new proposed configuration of NCL in terms of understanding thermal hydraulics using 3-D CFD simulations. Further, it also incorporates optimization of the proposed design configuration using formulated heat transfer model. The optimized geometry is simulated using 3-D CFD simulation which gave the desired rating. (C) 2018 Elsevier Ltd. All rights reserved.