Abstract: A master batch pellet comprises a thermoplastic resin and 2.0 to 60% by weight of a white combustion catalyst blended in the thermoplastic resin, the white combustion catalyst comprising composite particles obtained by carrying 0.001 to 0.10% by weight of metallic Pd colloid particles having an average particle diameter of not more than 10 nm on surface of respective inorganic carrier particles having an average particle diameter of 0.1 to 1.0 ?m and composed of at least one selected from the group consisting of aluminum oxide, silicon oxide, calcium carbonate and titanium oxide. The master batch pellet of the present invention is suitable for producing a thermoplastic resin composition exhibiting an excellent combustion-promoting effect, more specifically a thermoplastic resin composition which is promoted in complete combustion upon incineration thereof and effectively inhibited from generating harmful organic substances.

Abstract: Disclosed herein are a process for producing acicular goethite particles comprising the step off: blowing an oxygen-containing gas into a ferrous salt reaction solution containing colloidal ferrous hydroxide or iron-containing colloidal precipitates which is obtained by reacting an aqueous ferrous salt solution with less than one equivalent of an aqueous alkali hydroxide solution, an aqueous alkali carbonate solution, or an aqueous alkali hydroxide and alkali carbonate solution based on Fe.sup.

Abstract: Disclosed herein are a process for producing acicular goethite particles comprising the step of: blowing an oxygen-containing gas into a ferrous salt reaction solution containing colloidal ferrous hydroxide or iron-containing colloidal precipitates which is obtained by reacting an aqueous ferrous salt solution with less than one equivalent of an aqueous alkali hydroxide solution, an aqueous alkali carbonate solution, or an aqueous alkali hydroxide and alkali carbonate solution based on Fe.sup.