web.Method = "POST";
            web.ContentType = "text/xml;charset=utf-8";
            web.Accept = "text/xml";
            web.Headers.Clear();
            web.Headers.Add("SOAPAction", url);

            X509Certificate2 certificado = ObterCertificado();
            if (certificado != null)
            {
                ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;
                web.ClientCertificates.Add(certificado);
            }

            var soap = "<?xml version='1.0' encoding='UTF-8'?>";
            soap += "<soap12:Envelope xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns:xsd='http://www.w3.org/2001/XMLSchema' xmlns:soap12='http://www.w3.org/2003/05/soap-envelope'>";
            soap += "<soap12:Body>";
            soap += "   <cteDistDFeInteresse xmlns='http://www.portalfiscal.inf.br/cte/wsdl/CTeDistribuicaoDFe'>";
            soap += "       <distDFeInt xmlns='http://www.portalfiscal.inf.br/cte' versao='1.00'>";
            soap += "           <tpAmb>1</tpAmb>";
            soap += "           <cUFAutor>91</cUFAutor>";
            soap += "           <CNPJ>00000000000000</CNPJ>";
            soap += "           <distNSU><ultNSU>000000000000000</ultNSU></distNSU>";
            soap += "       </distDFeInt>";
            soap += "   </cteDistDFeInteresse>";
            soap += "</soap12:Body>";
            soap += "</soap12:Envelope>";

            // soap = "<cteDadosMsg><distDFeInt xmlns='http://www.portalfiscal.inf.br/nfe' versao='1.00'><tpAmb>1</tpAmb><cUFAutor>35</cUFAutor><CNPJ>000000000000000</CNPJ><distNSU><ultNSU>000000000000002</ultNSU></distNSU></distDFeInt></cteDadosMsg>";

            var byteArray = Encoding.UTF8.GetBytes(soap);
            web.ContentLength = byteArray.Length;
            using (var stream = web.GetRequestStream())
            {
                stream.Write(byteArray, 0, byteArray.Length);
            }

            using (var webResponse = (HttpWebResponse)web.GetResponse())
            {
                using (var stream = webResponse.GetResponseStream())
                {
                    retorno = new StreamReader(stream).ReadToEnd();
                }
            }