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Environmental awareness in both the public and regulatory sectors has necessitated proper treatment of medicinal components-rich pharmaceutical effluents. Even the presence of trace antiseptic may cause adverse health effects including development of "product resistant microbes" in the aquatic environment. The present study involves photomineralization of chlorhexidine, which belongs to the class of antiseptic drug components. This study details investigations on photocatalytic degradation of chlorhexidine in a slurry batch reactor using titanium dioxide photocatalyst. Emphases were given to study the effects of operating parameters on the degradation behavior of the targeted compound and characterization of degraded products. About 68.14% removal of chlorhexidine digluconate (CHD) was found after 1 h at 25 °C with a substrate-to-catalyst ratio of 2.5:1 under UV intensity of 50 μW•cm −2 at pH 10.5. Though the product profile illustrates several degraded products, toxicological analysis on Bacillus subtilis exhibited no inhibition zone, suggesting the eco-friendly nature of the degraded products.

In recent years, the occurrence of persistent organic compounds in industrial as well as municipal effluents is becoming a serious threat to the environment. The detrimental effects can be minimized with the help of photocatalysis.

Soil needs simultaneous replenishment of various nutrients to maintain its inherent fertility status 22 under extensive cropping systems. Replenishing soil nutrients with commercial fertilizer is 23 costly. Among various fertilizers, deposits of potassium (K) ore suitable for the production of 24 commercial K fertilizer (KCl) are distributed in few northern hemisphere countries (Canada, 25 Russia, Belarus and Germany) which control more than 70% of the world's potash market. Naturally occurring minerals, particularly silicate minerals, could be used as a source of K, but not as satisfactorily as commercial K fertilizers. In this context, bio-intervention (in combination with microorganisms and/or composting) of silicate minerals has been found quite promising to improve plant K availability and assimilation. This is an energy efficient and environmentally friendly approach. Here we present a critical review of existing literature on direct application of silicate minerals as a source of K for plant nutrition as well as soil fertility enhancement by underpinning the bio-intervention strategies and related K solubilization mechanisms. An advancement of knowledge in this field will not only contribute to a better understanding of the complex natural processes of soil K fertility, but also help to develop a new approach to utilize natural mineral resources for sustainable and environmental friendly agricultural practices.