in water powdered celestine was suspended in water, addn. of equimolar amount of Na2CO3, addn. of CO2 under 8 atm pressure at 175 °C; fast and quantitative reaction;;
in water powdered celestine was suspended in water, addn. of equimolar amount of NaHCO3, addn. of CO2 under 8 atm pressure at 175 °C; fast and quantitative reaction;;
2-mercaptoethanamine in water High Pressure; Sr(CH3COO)2*3H2O, NaOH and 2-aminoethanethiol added into distilled water; stirring for 5 min; soln. transferred into a Teflon-lined stainless-steel autoclave; hydrothermal treatment at 120-180°C for 12 h; product filtered out, washed with distilled water and ethanol in subsequence, and later dried in a vacuum oven at 60°C for 12 h;
