... , sulfur, ammonia, nitrogen and other substances;2,Add less (CO2 hardening process was 3.5% ~4.5%, ester hardening process ... 1.8%~2.5%);3,Sand process with good performance, gas is small, easy collapsibility;4,Use non-toxic, tasteless, ... with environment-friendly, resource-saving and green casting requirements.SOSIDER SERIES MIDIFIED SODIUM SILICATE22ORGANIC ESTERS2 hardening process & G01 Matching use. ...