Long acting fertilizer prodn. from acidic tars or resins - by neutralising with alkaline substances having fertilizer activity

摘要

Long-acting fertilizers are produced from acidic tars and acidic resins obtd. in the refining of lubricant oils and in the regeneration of used oils by treatment with conc. sulphuric acid. The acidic tars or resins are neutralized by stirring into aq. solns. of alkaline substances having cations with fertilizer activity. The resulting mass is filtered off and compressed into suitable shapes. The surface of the moulds is pref. previously dusted with chalk flour to prevent sticking. Process utilises starting materials the disposal of which would otherwise lead to pollution problems. The sulphur content of the tars and resins has a useful fertiliser effect. Weathering of the product leads to slow release of the fertiliser components and the carrier itself gradually breaks down to a dark crumbly material which has a favourable loosening effect on the upper layers of the soil and favourably influences soil mechanics. In an example, acid tar was added portionwise to a stirred suspension of CaCO3 in water, then further CaCO3 was added, the mixt. was stirred, and further CaCO3 was added to improved agglomeration. The product was a crumbly material.