A recycling process for achieving near-zero emissions of tannery effluent is characterized in that effluent recycling is carried out independently in soaking, liming, re-liming, de-liming bating, pickling chrome tanning, re-tanning, neutralizing, and dyeing procedures. The effluents in the above procedures can be recycled in each step. This process greatly reduces effluent discharge and helps solve the problem of tanning pollution. The process also improves the quality of the finished leather, effectively decreases loose grain rate and increases compactness and fullness of the finished product. The project can reduce chemical material consumption by 15%-55%. For example, the consumption of chromium powder can be reduced up to 65%. Consumption of other chemical materials can be reduced by more than 90%, while certain chemical materials can be essentially completely conserved.

A recycling process for achieving near-zero emissions of tannery effluent is characterized in that effluent recycling is carried out independently in soaking, liming, re-liming, de-liming bating, pickling chrome tanning, re-tanning, neutralizing, and dyeing procedures. The effluents in the above procedures can be recycled in each step. This process greatly reduces effluent discharge and helps solve the problem of tanning pollution. The process also improves the quality of the finished leather, effectively decreases loose grain rate and increases compactness and fullness of the finished product. The project can reduce chemical material consumption by 15%-55%. For example, the consumption of chromium powder can be reduced up to 65%. Consumption of other chemical materials can be reduced by more than 90%, while certain chemical materials can be essentially completely conserved.

A method of preparing hydrophobicizing leather treatment compositions includes the steps of a) free-radically initiated copolymerization of i) at least one ethylenically unsaturated carboxylic acid or its derivatives, and ii) at least one (meth)acrylate of a primary saturated C.sub.8 to C.sub.22 alcohol, b) mixing the reaction mixture obtained after step a) with water, c) salting at least some of the carboxyl groups of the reaction mixture obtained after step b) with a base, and d) shearing the reaction mixture obtained after step c) to an average particle size of 0.05-10 m,
wherein step a) is carried out in oil as reaction medium and wherein the atmosphere in step a) contains less than 0.1% by volume of an oxidizing gas.

The present invention relates to the use of reactive colourless and metal-free protein cross-linking agents for the cross-linking (tanning) of protein-containing substrates, said agents are environmentally friendly and give an improved fixation yield, a long-term cross-linking (tanning) stability and good washing off properties. The present invention further relates to processes for the cross-linking (tanning) of protein-containing substrates thereby creating an environmentally friendly process which minimizes the use of chemicals and further improves the quality and efficiency of the tanning and dyeing process.

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Methods, compositions, kits and systems disclosed herein can be directed to engineered cells for producing synthetic leathers, artificial epidermal layers, artificial dermal layers, layered structures, products produced therefrom and methods of producing the same.

Methods, compositions, kits and systems disclosed herein can be directed to engineered cells for producing synthetic leathers, artificial epidermal layers, artificial dermal layers, layered structures, products produced therefrom and methods of producing the same.

A recycling process for achieving near-zero emissions of tannery effluent is characterized in that effluent recycling is carried out independently in soaking, liming, re-liming, de-liming bating, pickling chrome tanning, re-tanning, neutralizing, and dyeing procedures. The effluents in the above procedures can be recycled in each step. This process greatly reduces effluent discharge and helps solve the problem of tanning pollution. The process also improves the quality of the finished leather, effectively decreases loose grain rate and increases compactness and fullness of the finished product. The project can reduce chemical material consumption by 15%-55%. For example, the consumption of chromium powder can be reduced up to 65%. Consumption of other chemical materials can be reduced by more than 90%, while certain chemical materials can be essentially completely conserved.

A recycling process for achieving near-zero emissions of tannery effluent is characterized in that effluent recycling is carried out independently in soaking, liming, re-liming, de-liming bating, pickling chrome tanning, re-tanning, neutralizing, and dyeing procedures. The effluents in the above procedures can be recycled in each step. This process greatly reduces effluent discharge and helps solve the problem of tanning pollution. The process also improves the quality of the finished leather, effectively decreases loose grain rate and increases compactness and fullness of the finished product. The project can reduce chemical material consumption by 15%-55%. For example, the consumption of chromium powder can be reduced up to 65%. Consumption of other chemical materials can be reduced by more than 90%, while certain chemical materials can be essentially completely conserved.

A composition including an acetal of an aldehydic tanning agent for tanning hides and/or pelts, as well as a method for tanning hides and/or pelts in order to produce leather, wherein an acetal of an aldehydic tanning agent is used. By reducing the pH, the aldehydic tanning agent can be released, whereby a tanning step is initiated. The composition according to the invention and the method according to the invention are characterized by lower toxicity compared to conventional compositions and tanning methods based on aldehydic tanning agents. Furthermore, improved penetration of the tanning agents into deeper layers of the hide and/or the pelt is possible, so that particularly homogeneous tanning is achieved.

The invention relates to a poly silsesquioxane-acrylic nanocomposite auxiliary for leather process and its preparation method. By mixing octavinyl silsesquioxane, organic solvent, ammonium persulfate, distilled water and surfactant in one system, and adding acrylic acid dropwise into the mixing system, cooling to adjust pH to obtain poly silsesquioxane-acrylic nanocomposite auxiliary for leather process. The auxiliary obtained in this invention is easily to penetrate into gap of the collagen fibers, and forms nano and micro-scale combination with the leather collagen, which can further improve the multi-point combination of the acrylic polymer with the collagen. Thus, the filling property of the leather that treated by the auxiliary is improved without affect the yield of leather, and the chromium content in the waste water is significantly reduced.