This paper presents the findings of a study of gas emissivity and the volumetric gas flow rate from a patented modified cellulose mix used

in production of disposable sand casting moulds. The modified cellulose mix with such additives as expanded perlite, expanded

vermiculite and microspheres was used as the study material. The results for gas emissivity and the gas flow rate for the modified cellulose

mix were compared with the gas emissivity of the commercial material used in gating systems in disposable sand casting moulds. The

results have shown that the modified cellulose mix is characterized by a lower gas emissivity by as much as 50% and lower gas flow rate

per unit mass during the process of thermal degradation at the temperature of 900°C, compared to the commercial mix. It was also noted

that the amount of microspheres considerably affected the amount of gas produced.